Ph and Fertilizer

Fertilising Smart Guide

Fertilising belongs to one of the most important gardening duties - especially outdoor and, of course, in hydroponics too. Yetmany cannabis cultivators do not know when the right time is to fertilise, how much to use, or how often. This is in part alsocaused by the lack of information supplied by the companies selling the fertiliser. To further complicate matters therecommended dosages are often quite confusing and tempt customers to use large amounts of fertiliser! If cultivators lackexperience or, despite a good amount of gardening knowledge, they cannot find the cause of certain plant symptoms, it is verylikely that they are constantly over-fertilising the plants.

To put an end to this negative trend, and because our strains grow perfectly well with only small amounts of fertiliser, we wouldlike to share important tips from our many years of cultivation experience. By following these guidelines fertilizing your plants canbecome a secure routine and not a matter of life and death for your plants*.

* * Mandala Seeds shall not be responsible for the use of any information herein presented and you mustmake your own decision as to its suitability and completeness for your use. We are not responsible forthe use of a product mentioned and any effects or consequences it may have on your cultivation.

Extra notice: this guide has been updated and expanded August-September, 2010. We have made an effort to present the old and

new information in easy to understand and straightforward steps & guidelines. We hope that it benefits you in your cultivation &

studies on cannabis and the Mandala strains in particular.

What's Special About Mandala Genetics

To start with we would like to introduce you to some of the special features of Mandala strains. This is particularly importantinformation for growers who are accustomed to growing commercial strains that are mainly standard inbred genetics.

Nutrient efficiency vs nutrient sensitivity

Mandala Seeds is the first seed bank to introduce the concept of "nutrient efficiency" and breed with this goal in mind. Nutrientefficient plants have the ability to assimilate and fertilisation nutrients quickly, efficiently, and naturally. This enables amazingstress-free cultivation if you are not going to interfere with this natural potential. The vigour and robustness of our strains ensuresthat mistakes can be forgiven. Mandala plants can bounce back quickly if there is a period of deficiency or drought.Over-fertilisation also does not kill them as quickly as with weaker genetics.

For indoor cultivation Mandala plants can grow and flower in soil from start to finish without extra fertilizing. How this can be doneis explained in detail in our SOIL GUIDE.

Nutrient sensitive plants are common in genetics weakened by what is know as "inbreeding depression": repeated self-breeding andinbreeding. They are also common among strains created by poor breeding and seed production practises such as random crossesand pollination, inferior parent selection, low quality control, etc. In addition, long-term hydroponic generations gradually becomegenetically conditioned to grow under synthetic feeding and start to loose certain abilities in self-sufficiency. Unfortunately, asubstantial amount of mainstream strains fall under these categories. Nutrient sensitive plants do not have the natural ability forfast and vigorous growth and require long vegetative growth periods for their development, root development is slow orinsufficient, they do not grow abundantly in soil without extra feedings, and so on. Many nutrient sensitive plants do not performsatisfactorily unless they are grown hydroponically and may require high nutrient levels. On the other hand, such strains/plantstend to be finicky. They may constantly alternate between showing deficiencies and symptoms of over-fertilisation, or both at thesame time.

Energy-saving genetics

This is another typical Mandala concept: energy-saving genetics mean that you save time, money, and energy on growing.

Fast growth cuts down vegetative time. You save money on electricity, water, wear & tear of grow equipment.

Nutrient efficiency cuts spending on fertiliser, which is also environmentally friendly (fertiliser production & run-off is a #1environmental killer).

Hereditary vigour and health cuts spending on any additional plant products that the industry tries to sell to you, because you

Marijuana Fertilizing http://www.mandalaseeds.com/Guides/Fertilizing-Smart-Guide

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certainly won't need them for natural development.

All factors combined allow for great harvests on soil with less need to invest in hydroponic systems to get a big crop. This savesyou a lot of money on expensive equipment, enables low maintenance cultivation, and you can later recycle your soil in a gardenor compost and give back what you borrowed from nature.

How this should be applied in your cultivation methods

Successful gardening cannot be bought in a bottle. Mainly ignore what the multi-billion dollar agrochemical industry istrying to sell to you. They don't even test their products scientifically on large-scale marijuana plantations. Focus on theessentials because that is all your plants need.

Keep it simple. Mastering simplicity is the foundation of gardening. It makes you learn from your plants. Once you haveachieved this you can proceed to more complicated cultivation methods.

Your plants know how to grow! They have been doing it since thousand of years. The less you interfere in naturaldevelopment the better the results. Learn how to assist your plants with basic, but essential, gardening tasks.

Learn how to grow you Mandala plants indoor in soil with no extra fertiliser or only minimal feedings to top-up nutrients.This is the easy plant care that they were created for! Read our guides for expert tips on how this can be achieved in easysteps.

Manage your hydroponic cultivation with low to medium range EC levels (i.e. approx. EC 1.0 mS/cm based on a starting EC of

0.4-0.5 mS/cm). You will be surprised how healthy and big your crop is. Overfeeding is a chronic problem in cannabis gardensthat leads to prematurely shortened flowering times, lower yields, poor calyx-leaf ratio, bud mold, pest susceptibility,

inferior aroma/taste, and increased pollution from fertiliser run-off.

EC Meter

Essential Knowledge About Nutrient Dosage

How We Fertilise During Growth (Soil)

How We Fertilise During Flowering (Soil)

Hydroponics and EC

Product Recommendations

Products With Uncertain Benefits

Purchasing Guidelines

Avoiding Misdiagnosis/Symptoms of Overfertilization

Common Mistakes

EC meter

If you ever need to fertilise it is essential to mix the correct dosage using an EC meter.

Do NOT blindly follow instructions printed on the fertiliser product or a conventional "feeding schedule" from themanufacturer.

The word “EC” stands for electrical conductivity. Pure distilled water conducts no electrical current. But once you add mineral saltsto it this changes. Tap water, rainwater and well water will also contain traces of minerals and this will show on an EC meter. Thefirst step is to always measure the EC of your water source so that you know how pure it is or if it is contaminated with a lot ofminerals. If the EC is over 0.6 mS/cm you should consider using cleaner water. Read our WATER & PH Guide for more info.

Nutrient salt concentrations are measured by their ability to conduct electricity through a solution. If you do not know howconcentrated the nutrient solution is that you intend to give to your plants you are gambling in a life and death situation. One fatalmistake can seriously damage or kill your plants. Therefore you must know three things before you even consider fertilising:

1. What the EC is of the water (this is called the “starting EC”).

2. What EC your plants can easily tolerate.

3. What the EC is when you add a measured amount of fertiliser to it and if this is within the range of tolerance (this is called theEC of the “nutrient solution”).

Buying an EC meter

We recommend that you buy an inexpensive EC meter such as the 45$/Euro model fromMilwaukee or Hanna. This is perfectly sufficient and rarely breaks down. You need tocalibrate your EC meter every once in a while. For this you need calibration fluid (grow shop)and a simple thermostat (pharmacy).


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Read our Quick Start Guide for advice on the complete essential gardening kit.

What to watch out for

There are various other scales or measurement systems used to measure the EC. These are called CF (conductivity factor), ppm(parts per million), and TDS (total dissolved solids). North American growers tend to use ppm and European growers use EC.

The problem with these other measurement systems is that they are all based on the EC but the manufacturers then use their ownsystem of conversion to convert the EC to ppm, TDS or CF. These conversions are not as accurate as when you simply measure thenutrient salts with an EC meter in the first place! This means that each tester/meter will give you a different reading. You cannottell what the EC is when you use a TDS or ppm meter. You cannot even compare readings between a TDS or ppm meter fromdifferent manufacturers!

Other systems make it very difficult to provide advice and for growers to compare information on their fertilizing methods anddosages. That’s why we always recommend to purchase an EC meter and avoid this confusion. You can then easily follow our adviceon fertilizing and you always get accurate readings.

EC meters are available in two versions: milliSiemens (mS/cm) and microSiemens (µS/cm). All readings used in our guides are inmillisiemens (mS/cm). Here is a conversion table for calculating the value in millisiemens. The conversion is quite simple: 1mS/cm= 1000 µS/cm.

If you already have an expensive ppm or CF meter that you want to keep using, there may be a conversion table available online forsome popular meters.

Essential Knowledge About Nutrient Dosage

Let's start with the small print on the bottles which your would generally use as orientation for mixing your nutrient solution.

What many do not know: the recommended EC value is always based on osmosis water with an EC of 0.0 mS/cm!

Example: Ionic recommends an EC of 2.0 mS/cm for flowering in hydroponics. From this value the cultivator must deduct the EC ofthe tap water in order to calculate the actual recommended dosage.Let's say your water has an EC of 0.6 mS/cm. Then you calculate 2.0 – 0.6 = 1.4 mS/cm.The recommended maximum dosage is therefore 1.4 mS/cm.

Canna and other Dutch companies generally recommend even higher values. So the necessity of being aware of this formula isquite apparent. Although one really must ask how the plants should survive long term on levels of 2.0 – 2.2 mS/cm, most customersactually use such strong dosages in their grow because they are unaware of this essential information. The result is not only a wasteof fertiliser in hydroponic systems. Plant care also becomes much more complicated and problematic. Regular flushing with wateror weak nutrient solution are necessary at such high EC levels in hydroponics. On the one hand, the plants grow very fast (theystretch, get leafy, etc.), and, on the other hand, they develop complex symptoms of over- and under-fertilisation from the high saltcontent in the substrate.

In the end massive overdoses of nutrients lead to a high risk of mold in the flowering phase, reduced levels of resistance againstpests, lower yields, male flowers on females, and possibly pose a health risk from radioactive traces in the cannabis (fromphosphate).

For the cultivation in soil there is a common rule among cultivators to use 50% of the recommended dosages. Growers follow thisrule without actually knowing what salt concentration they are feeding their plants with. For soil cultivation an EC meter is themost important tool to find out what the proper dosage is. This is why everyone who values their plants should not save on thisrather moderate investment of 45$/Euro!

Testing Dosages Given by The Industry

To demonstrate how important the EC level is we have tested 5 popular types of fertiliser. Only the fertiliser for flowering wasselected because during this phase growers fertilise the most (after the motto: more fertiliser = more yield). Yet during this part ofthe life cycle plants become increasingly sensitive to excess mineral salts.

Before we look at the results it is important to understand one thing: generally one should never fertilise more than 0.8 mS/cm onsoil. You can fertilise up to 1.2 mS/cm if you have to quickly reverse deficiencies in adult outdoor plants. It is better to fertilisewith a medium range and repeat the treatment after a week or so, rather than starting with a heroic dosage that can be difficultfor the plants to cope with all at once. For indoor we recommend 0.65-0.7 mS/cm for all Mandala strains that need to be fertilised.

The first important step is to find out what the EC of your tap water is. In this example we are using a 50-50 mix of reverse osmosiswater and normal tap water to get 0.43 mS/cm. Obviously, if you have a value over 0.8 in your tap water you have to lower the EC


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level through filtration. For small gardens it's sufficient to use a Britt Filter if you do not have the money to buy a householdreverse osmosis filter (approx. 100$/Euro). The Britt filter can reduce the EC level by 0.15-0.20 mS/cm. Another alternative wouldbe to buy 5L/1 gallon bottles of non-carbonated mineral water when you fertilise. Good mineral water has approx. 0.25 mS/cm.

Here are the test results on our water with EC 0,43 mS/cm for 5 popular products (measured on Hanna Dist 3 meter). Allvalues are in milliSiemens (mS/cm).

General HydroponicsOne Part Bloom (N-P-K: 2-4-7)

Recommended min. dosage (Hydro): 8ml/1L or EC 1.5 mS/cmRecommended dosage on soil: "less" (?!)Recommended frequency on soil: every second watering2ml/1L = 1.30 EC4ml/1L = 2.00 EC0,5ml/1L= 0.70 EC

The amazing thing about these instructions is the inaccuracy of the amount to fertilise on soil. What does "less" mean? If we were touse the common rule and mix 50% of the recommended dosage we still get an EC of 2.0 mS/cm! That would lead to immediatesymptoms of overfertilization. Even at 25% of the dosage we are still in the danger zone. With 0,5ml/L or 6% of the recommendeddosage we finally have a safe solution! This example shows how important it is to have an EC meter at hand.

CannaTerra Flores (N-P-K: 10-9-19)

Recommended dosage: 5ml/1LRecommended frequency: 1-3 x weekly5ml/1L = 1.83 EC2ml/1L = 1.05 EC1ml/1L = 0.76 EC

Out of interest we tested the dosage of 5ml/L. If you were to give your plants this dosage they would not be very happy about it.Surprisingly, the manufacturer recommends this high salt level for soil cultivation – a level that is not even used in most hydroponiccultivation! The ratio of nitrogen and potassium is quite dangerous in this fertiliser. Both minerals are present in high amounts butflowering cannabis plants cannot store excess N and K as easily as phosphorous and magnesium. At 20% of the recommended dosagewe can water with a safe nutrient solution.

IonicBloom (N-P-K: unknown)

Recommended min. dosage (Hydro): 7ml/1LRecommended dosage for soil: 1,0 mlRecommended frequency: no info3,5ml/1L = 1.62 EC1 ml/1L = 0.81 EC

At least the manufacturer offers an EC value for soil cultivation. But, again, if you don't have an EC meter and mix 50% of thedosage the plants are over-fertilised. At 15% we found the correct dosage. The downside is that the N-P-K values are not disclosedon the label which is below standard.

AlgoFlashFlower (N-P-K: 4-6-7)

Recommended dosage: 4ml/1LRecommended frequency: every second watering2ml/1L = 1.38 EC1ml/1L = 1.00 EC0,5ml/1L = 0.75 EC

This concentrated fertiliser is a good choice for cannabis cultivation – but it is also dangerously potent. Even half the dosage is stilltoo strong and it has to be diluted to 12,5% before we get the ideal value of 0.75 mS/cm. If you have a higher EC level in your tapwater you can water with only 10% and get good results.

All recommended feeding frequencies on soil for the fertilisers in our test are incredibly high. This is a general trend amongmanufacturers. Growers who follow the advice on the bottle or "feeding chart" automatically cause damage to their plants - even ifthese are not immediately visible for an inexperienced or untrained grower.


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Feeding frequency on soil

Apart from the actual salt concentration of the nutrient solution the frequency and amount you water is an important aspect.

Generally, cannabis plants prefer small but regular feedings if they require extra fertilisation. "Small" means in our case amoderate level of 0.6 mS/cm (indoor) to 0.8 mS/cm (outdoor). You can compare fertilizing to real mealtimes. People also get astomach ache when they overeat. It's much healthier to eat small meals regularly. In the same way cannabis appreciates gettingsmall portions of nutrients that can be "digested". So watering high dosages of fertiliser is like force feeding. But plants aren't pigsthat have to be fattened.

With a nutrient solution of 0.6-0.8 mS/cm you can't do much wrong unless you make a mistake with the feeding frequency oramount of nutrient solution. That's why it´s important to wait 7-10 days after fertilizing and observe the plants. How are theytaking up the nutrients? Do they need a bit more or are they looking healthy enough? A slight deficiency can be easily levelled outwith one mild feeding (and does not impair flowering) but overfertilization causes irreparable damage. As you learn to observe theplants you will develop an intuitive understanding and can read small signs of nutrient deficiency that signal the best time to applya mild nutrient solution.

Regular feedings such as once every 10-15 days are rarely required indoor unless you are growing in poor soil quality or using asmall container size. It is a major mistake to assume that Mandala plants automatically need regular feedings indoor on soil. Readour SOIL GUIDE and you can learn how to grow a great crop in soil without any extra fertilizing.

How we fertilise during growth

To provide the plants with many useful nutrients we first lower the EC level of the water to about 0.45 mS/cm. With this level weeither mix a nutrient solution of 0.65 mS/cm for indoor, or 0.75-0.8 mS/cm for greenhouse/outdoor.

Indoor:

All Mandala strains are grown in 5L/1.2 gallon containers with high quality soil that is enriched with worm manure orcompost. During the typical 4 week vegetative cycle they receive no extra fertiliser.

If individual plants show the need for a mild feeding they are given 1x a nutrient solution with NPK 5-6-7 or 4-8-6 and 0.65EC a few days before switching to 12/12. Nitrogen is used up fastest by Mandala strains due to their quick and vigorousgrowth. Nevertheless a complete NPK fertiliser is essential because there are also other nutrients which may need

replenishing. They will also play a role in facilitating the assimilation and use of other nutrients in the plants.

Individual plants may need nutrients to be topped-up after 4 weeks, because it will take another 7-12 days before thefemales have all shown sex and can be repotted into bigger containers and fresh soil. For this purpose a flowering fertiliserwith sufficient nitrogen is chosen. Fertiliser with a high % of nitrogen is not conducive to supporting flowering and can also

influence a higher ratio of male plants during sexing.

Large plants such as mother plants eventually require feedings every 2-3 weeks, for example, because there is a limit tocontainer size. We use an organic fertiliser such as CANNA Terra Vega for this purpose. This is a very concentrated fertiliserthat lasts a long time because only small dosages are needed. CANNA Terra Vega is assimilated quickly by plants and helps

in levelling out a deficiency (such as nitrogen) quickly. Read our SOIL GUIDE for advice on growing mother plants organically incontainers.

Greenhouse/Outdoor:

All Mandala strains are grown in high quality soil that is enriched with worm manure or compost. After 5+ weeks a mildfeeding is given to all container plants 1x with NPK 5-6-7 or 4-8-6 and an EC of 0.75-0.8 mS/cm. Plants grown in the grounddo not require extra fertiliser for a long period because we use high quality soil mixes.

How we fertilise during flowering

To provide the plants with many useful nutrients we first lower the EC level of the water to about 0,45 mS/cm. With this level weeither mix a nutrient solution of 0,65 mS/cm for indoor, or 0,75-0,8 mS/cm for greenhouse/outdoor.

Indoor:

The Mandala female plants are repotted into larger containers after sexing. The container size is adjusted to the size of theplants and their expected flowering time. Read our SOIL GUIDE for info on recommended container size.

Short flowering indicas and small strains do not receive any extra fertiliser during flowering unless an individual plantshows a mild deficiency.

Longer flowering sativas and sativa-indicas are given 1x a nutrient solution with NPK 5-6-7 or 4-8-6 and EC 0.65 mS/cm afterapprox.. one month of repotting. At this stage they are usually in day 45-50 of flowering. This is when significant waves ofnew bud development occur. Some nutrients have now been depleted to a certain level in the container and a liquid


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feeding can give the plants a boost. At 2-3 weeks before harvest the plants still have the energy to assimilate and utilise newnutrients.

As flowering reaches the final phase and the plant is nearing the end of it's life cycle a biochemical change occursand cannabis plants switch to using up mainly nutrients stored in the plant tissue/leaves. This is also accompanied with aminimised uptake of water. It is not recommended to fertilise anymore during this phase. This can cause premature wilting

of pistils, bud mold, or isolated male flowers in cannabis.

Greenhouse/Outdoor:

Container plants receive 2-3 mild feedings with a liquid flowering fertiliser and EC 0.7-0.75 mS/cm. The number offeedings depends on the length of flowering, plant size, and any signs of slight deficiencies that need to be compensated.

Plants in the ground are fertilised according to individual requirements. Strains or plants that are shorter, more early, orvery nutrient efficient will probably flower until harvest without any need for an extra feeding because we use highquality soil. Observation is the key to smart fertilising!

Greenhouse and outdoor plants are sometimes fertilised with a moderate dosage of granular time-release fertiliser. Wehave included some tips on using time-release fertiliser below.

In the last 2 weeks of flowering we stop fertilising and let the plants use up the stored nutrients in the plant tissue and soilnaturally. In the last weeks before harvest the plants are practically "dying" and absorb only small amounts of nutrients.

What you should watch out for

Soil and containers

The quality of the soil and size of containers decides a great deal about the nutrient needs of your plants. If you use stronglypre-fertilised soil it´s possible that your plants don't require any additional feeding till harvest! A good example are organic growsthat use composted material with a high mineral content (like manure, etc.). Some manufacturers sell very potent soil mixes thatare almost toxic in their pure form. An example is All-Mix from Plagron which has an EC of 2.4 mS/cm! If your containers are toosmall compared to plant size or maturity you will find that your plants quickly suffer from nitrogen deficiency. Another factor islight intensity. A fluorescent grow cannot be compared to a sodium vapour grow. More light means bigger plants and higher nutrientrequirements. Read our SOIL GUIDE for advice on soil quality and container size.

Watering amount

Not only the EC but also the amount of nutrient solution determines salt levels in the soil. The amount you water should not exceedthe normal requirements of the plant. If an adult cannabis plant in your garden uses 500 ml water daily then you should water thatsame amount or less with the nutrient solution. Never fertilise on dry soil!

Outdoor

Outdoor the quality of the soil, plant size, and climate play an important role in nutrient uptake. It's best to fertilise whenwarm/sunny days are predicted so that the plants can transform the nutrients directly into growth. Due to plant size the mostcommon deficiency is nitrogen. This deficiency is easy to detect: first the leaves lose their leaf shine and become dull, then thelower sun leaves start to yellow, these symptoms gradually move upward and affect more leaves, in advanced stages the lowerleaves dry up and die and the plant has yellowed up to the shoot tips. A flowering fertiliser with an adequate amount of nitrogenshould be used when nitrogen deficiency appears during or after sexing. When a deficiency is already apparent you can use ahigher EC of about 0.9-1.0 mS/cm to compensate the low level of nutrients quickly.

The second most common deficiency is phosphorus which is required in large amounts for root and bud growth. Phosphorous isstored generously in plant tissue so that if you have an intelligent feeding plan the plants will get enough phosphorous to last tillharvest even when feeding stops about 2-3 weeks beforehand.

Hydroponics and EC

Use an EC at the low-medium range (i.e. EC 1.0-1.6 mS/cm). This recommendation is based on a starting EC of 0.4-0.5 mS/cm ofyour water. Adjust accordingly if your water has a very different EC and consider purifying your water if the EC is high. Duringflowering most Mandala strains can be grown with approx. EC 1.0-1.2 mS/cm. The best EC for your hydroponic setup has to bedetermined by yourself through practise and observation. There is no standard guideline.

The optimal EC depends on many factors such as:

the choice of strain

the stage of the plant's life cycle (seedling, young adult, early flowering, late flowering; adult mother plant; seeded plant)


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light intensity

style & frequency of watering

how the nutrient solution is replenished

water quality

temperature

CO2 supplement

pH fluctuation

substrate used

fertiliser brand and NPK ratio

As you can see there are many factors that play a role in nutrient uptake and nutrient demand!Be prepared to adjust the EC once any of the above factors change significantly. For example, nutrient demand changes iftemperature fluctuates and an EC that is perfect in summer may need to be modified during winter months.

You will be surprised how little fertiliser is required to grow our high performance strains. Mandala plants are bred to utilisenutrients extremely efficiently (not to be confused with nutrient sensitivity). They are not finicky... as hydroponic cultivationsmaintained on high EC levels have proven. Our strains are tuned for optimal performance. Their profuse root growth, thick stems,and large leaves function as super-highways and storage houses for the uptake, assimilation, and storage of nutrients.

Remember: You can always adjust your EC upwards a bit if required...but you can't reverse damage from overfeeding.

By using an EC level that sufficiently provides for your plants without going over the top you will have a less care-intensive growtime, save $$ on fertiliser, achieve even higher yields and optimal calyx-leaf ratio, and enjoy better tasting herb.

Product Recommendations

Always purchase high quality fertiliser from reputable companies such as General Hydroponics, Hesi, Bio Bizz, Canna, AlgoFlash,Compo, Fox Farm, etc. With such fertiliser brands you will have the guarantee of a product that contains high grade minerals andnutrients that are easily absorbed by the plants. Some brands also carry a quality seal.

Fertiliser is not expensive when used at the proper dosage. All of the fertilisers we tested can be used as long as the dosage iscorrect. Among the many products offered there are differences in quality concerning how easily nutrients can be assimilated bythe plants and also the NPK ratio. In particular the NPK ratio is, unfortunately, not optimised for cannabis plants in quite asubstantial number of products. It is common that fertilisers contain too much potassium (K) for the flowering phase. This has beenan issue since decades. Part of the problem is that most manufacturers do not test their products scientifically on large-scalemarijuana plantations due to the legal challenges involved. At the end of the day it is not the same to compare marijuana withtomatoes, cucumbers and yucca plants (it is also unscientific to put out a product for the general public to test due to a completelack of control over the situation and unverifiable data). Although potassium is theoretically important for flowering it is also easilyoverdosed because cannabis does not have such a large tolerance for this mineral as for phosphate (P). Symptoms of potassiumover-fertilisation are quite common in hydroponics and, even if diagnosed correctly, you cannot reduce the potassium level unlessyou have an alternative fertiliser with less K. Therefore, we particularly recommend products with a balanced P-K ratio, such as inNPK 4-6-6 or 3-7-6, and so on.

Our top product tips:

CANNA BioVega (Soil)

CANNA is one of the most serious companies on the market with decades of experience. They are alsoone of the few companies who actually test and develop their products scientifically on cannabis (whata surprise!). BioVega has become our prime choice in the vegetative phase such as for preserving ourparent plants. It is very potent - a thick organic liquid that requires only minimal dosage. As such, greatvalue for money. One bottle can last years if it weren't for the expiry date (always watch out for this onorganic products).

Although CANNA mentions that this product cannot be overdosed we have observed quite the opposite.An EC meter is highly recommended so that you don't overdose. Please follow the general guidelines forfertilizing on soil as outlined in this guide and also consult our SOIL GUIDE, because you may not needto fertilise at all during the growth phase. Due to the potency of this fertiliser you should be verycareful not only with the dosage (EC), but also the frequency of using this product on soil. It also plays a

role how much light the plants are getting. If a plant is standing in a darker corner of your indoor grow space it may react moresensitively than a plant near or under the lamp. This is because it is not receiving enough light to utilise the extra nutrients forgrowth. Adjust the dosage or amount you water accordingly. Do not fertilise under low-light unless you have made a major mistakeand the plants are seriously undernourished. BioVega contains highly absorbable betaine nitrogen which can cause leaf burn or leafdrop if not used properly. Also make sure you are not fertilising during critical periods, such as when flowering commences, as thiscan cause undesirable side-effects.

The nutrient absorption is good but you should give your plants a few days to show how they have taken up the nutrients. BioVega isexcellent for topping up nutrients once plants are getting root bound, for maintaining large mother plants, keeping potted plantsfresh and green outdoor or in a greenhouse, etc.


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BioVega is one of the few products on the cannabis market that is certified organic (OMRI) and has several European organicaccreditations. The OMRI Listed® seal assures the suitability of a product for certified organic production. More info on the CANNAbio products can be found here: http://bio.canna-uk.com/bio/indexphp.php

Special note: although we have also tested CANNA BioFlores it did not convince us as much as BioVega. There are alternatives (seebelow).

GENERAL HYDROPONICS FloraNova Bloom (Soil/Hydroponics)

This is what we have been waiting for since a looong time! Finally, a well-balanced NPK ratio of 4-8-7that is perfectly suited for cannabis during all stages of flowering, and also for topping up nutrientsbefore or during sexing in soil. We tested the new product outdoor and found it to be an excellentfertiliser which is "soft" on the plants. Nutrient uptake is very easy and effective and holds up to theoptimum nutrient absorption as advertised by GH.

The price-quality ratio is equally impressive. This fertiliser is highly concentrated and only a smalldosage is needed for soil cultivation. We used just one bottlecap per 6-7 Liters of water to feed pottedplants and plants in the ground. This potency makes it an attractive choice for cost-intensive hydroponiccultivation too. Certainly the NPK ratio of FloraNova Bloom is a clear improvement to the 3-part Flora

Series from GH. FloraNova Bloom is based on mineral and organic sources but looks and smells like a rich organic fertiliser. Thebottle needs to be shaken well to mix the contents properly before each use.

CANNA AquaVega & AquaFlores (Hydroponics)

A good choice for the European hydroponic market.

CANNA Coco (Hydroponics)

Probably the best selection of products for growing in coco coir.

Extended-time release fertiliser

Extended-time release fertiliser is an option for greenhouse/outdoor cultivation. It can be particularly practical if your cultivationarea is located further away from your residence and you do not have the possibility to tend to the plants regularly. Cultivation inthe ground with poor soil quality also benefits from this type of feeding. Whenever possible you should at least dig a hole for youngplants and fill that up with quality potting soil/compost.

There are organic and mineral based products in powder or granular form.

When using extended-time release fertiliser you should follow some guidelines:

organic: make sure that the nitrogen is slow acting

mineral: do not buy double-digit NPK formulas such as 15-30-15

always test a product beforehand on other flowering plants in your garden and on 1-2 cannabis plants

start with a low dosage and observe reaction

Products with Uncertain Benefits


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We specifically warn against the incautious use of bud boosters on Mandala strains and cannabis plants in general. Root growthactivators can also do more harm than good on some plants. Due to the inborn vigorous root growth of Mandala strains such productsare unnecessary in the first place. The products listed below should be used with extreme caution, as they may simply be a wasteof money and some can even damage your crop. It is not uncommon that growers report undesired effects such as leafdiscoloration, bud mold, or an unsavoury taste when using some of the products listed below. Many products are never testedscientifically on significantly large marijuana plantations under controlled conditions. Some biological products contain no activeingredients due to expiry dates of the manufactured stock or poor quality. There are many pitfalls in the industry and you shouldalways exercise prudence when buying a product. Do not test it on all your plants at the same time and do not treat perfectlyhealthy plants. All our advice on measuring EC levels, providing basic & essential plant care, not interfering with naturaldevelopment & using common sense, leaving healthy plants do their own thing, applies to this subject.

root growth activators

flower activators/bud boosters like TopMax (can lead to over-fertilisation, premature end to flowering, bud mold,etc.)

humic acid extracts

vitamins (mainly harmless but also no proven benefits except as a possible prevention of mildew)

enzymes (may only be effective for coco coir recycling)

fermented plant extracts such as Bio Boost

Purchasing Guidelines

There are so many different products available worldwide that it is impossible to offer an overview or test them individually. That'swhy we are offering some simple guidelines. They give you more clarity to decide which product can be a suitable choice forcultivating your cannabis plants. These tips are not a bible or the last word on this subject. Treat it as a check list that can help youmake more sense out of the differences between products offered. You should read through this fertilizing guide beforehand sothat you understand some of the points below.

Finding a suitable product can be a process of trial and error. Ideally you should always test a new product on a sufficientnumber of plants to determine it's efficacy, quality, and method of use. A control group growing under the same circumstancesgives you more assurance about the results or any particular observations you may take note of.

Does the product have the correct NPK ratio for marijuana cultivation? (may require some math to work this out with 3-partfertilisers)

Does the manufacturer provide enough information on the product such as NPK ratio, composition, suitability for soil/hydro, expirydate on organic products, additional cultivation info on their website, etc?

Is the product recommended for your type of water: hard or soft water?

Is the product highly concentrated or overly dilute? (makes a big price difference in hydroponics or large-scale cultivation)

How fast-acting is the nitrogen, how much is the % of amoniacal nitrogen? (requires testing by you to be on the safe side)

How efficiently can the nutrients be absorbed by the plants? (requires testing by you to be on the safe side)

Is the product easy to use and complete or split into several parts? Decide which you prefer to narrow down the choice. If you area novice grower, have little time, or require easy plant care, you may not be comfortable with using a complicated chart forcombining various bottles in the correct order to mix the nutrient solution, and determining when to change the formulaaccording to certain phases of the plants life cycle.

Has this product been recommended by other growers? If so, first compare their cultivation method & environmental factors withyour's to determine how much of the feedback by others can be applied to your setup.

Does the company have internationally accredited products or received any notable product awards? This is an important guidelinefor manufacturing standards and quality comparison with other companies. "Awards" from cannabis trade fairs are not a guidelineas these are only superficial titles given to participating companies and do not reflect any scientific evaluation of the products.

Remain cautious about company marketing that "pushes" customers into buying subsidiary products, i.e. "additives". Often theseproducts are automatically included in feeding charts as if they are a necessary part of fertilizing or plant care - in particular forhydroponic cultivation. Products such as vitamins, amino acids, rooting activators, bud boosters, etc. fall under this category. Seethe section above on Products With Uncertain Benefits.

Avoid a product range that incorporates P-K 13/14. This extremely potent mix of phosphoric and potassium acid is a total overkilland one of the "evils" of the agrochemical industry. It is mined and produced in an environmentally detrimental way and puts asevere strain on cannabis plants when they are "forced" to flower. You can easily ruin a good crop with overfeeding P-K.

The best mantra for product choice...test, test, test! What is written on the product does not always translate into real liferesults. You do not know how the plants will react to the product unless you test it. Therefore, proceed in small and simple steps.Check out a new product on a test group before applying it to your most precious crop! If you have a garden you can even dopreliminary testing on any non-cannabis flowering plants. This is especially useful for finding the most suitable time-releasefertiliser as these can be very variable in their effects (such as how fast-acting the nitrogen is) and you may need to try out acouple of brands.

Avoiding Misdiagnosis


9 of 11 8/13/2013 8:52 AM

A regular occurrence in cannabis cultivation is that pH related symptoms are confused with deficiencies. The pH of your wateror nutrient solution must always be adjusted to the correct value. Please read our WATER & PH GUIDE for more details.

Some growers claim that their plants are thriving on very high EC levels and have noproblems whatsoever. There are mainly two reasons for this assertion:

1. These are strains that are genetically predisposed to grow under high amounts offertiliser (hydroponic generations, etc.)2. The cultivator does not recognise the negative symptoms/damage fromoverfeeding (this occurs quite often)

Even if your plants look nice and green for some time, as you continue to fertilisewith high EC levels eventually you will run into one or more of the followingsymptoms of over-fertilisation.

Symptoms of Over-fertilisation

leaf curl

leaf edge burn

necrotic (brown) spots on leaves

leaf wilting and leaf drop

withering shoots

multi-nutrient blockage

overly lush & shiny green foliage (usually combined with slow flowering)

"runaway" spindly & weak shoots

uncontrolled growth

slow root development

delayed flowering

high ratio of males

male flowers on females

elongated buds

leafy buds

sudden wilting of pistils

premature end to flowering

bud mold

increased pest susceptibility

Examples of some of the above mentioned symptoms.


10 of 11 8/13/2013 8:52 AM

DisclaimerContact

Common Mistakes

insecurity and worries about not getting enough yield

mistaking pH related symptoms with deficiencies

mistaking natural reddish-purple plant coloration for phosphorous deficiency

using recommended dosages of the product without measuring the EC

not deducting the EC of the tap water from the recommended EC

using high nutrient levels in hydroponics or soil to "force" growth or flowering

treating soil cultivation as if it offers no nutrients to the plants

using small containers of soil and compensating with a standard "feeding schedule"

combining low light cultivation with too much fertiliser

fertilising plants that are perfectly healthy (soil)

fertilising seedlings (soil)

fertilising plants prior to, or after, repotting in fresh soil

ignoring individual nutrient requirements of plants (collective feeding)

fertilising indoor with pure guano powder or pellets

fertilising outdoor flowering plants with pure guano or fish emulsion

using super-phosphate fertiliser, PK 13-14, or double digit NPK formula (i.e. 15-30-15 or similar)

combining bud boosters or PK 13-14 products with the nutrient solution

not testing new products on a small portion of plants first

© All rights reserved, Mandala Seeds Ltd. 2004 - 2012.

The complete design of this web site and all its contents and single components such as images, logo, text, etc. belong to Mandala Seeds. No unauthorized

copying, distribution, hiring and/or lending of our web pages or their contents is permitted without our written consent.


11 of 11 8/13/2013 8:52 AM

What are the best marijuana nutrients?

How Do You Choose Your Marijuana Nutrients?How Do You Choose Your Marijuana Nutrients?How Do You Choose Your Marijuana Nutrients?How Do You Choose Your Marijuana Nutrients?

If you're growing in soil, you will want to get nutrients made for soil.

If you are growing in any medium besides soil, like coco coir, or a soilless mix, you will want to

get nutrients specifically made for hydroponics. Some nutrients are even more specific, like

Canna Coco is formulated to work best growing weed in Coco Coir.

Looking for suggestions?Looking for suggestions?Looking for suggestions?Looking for suggestions?

Simple Nutrient System For Growing Marijuana in SoilSimple Nutrient System For Growing Marijuana in SoilSimple Nutrient System For Growing Marijuana in SoilSimple Nutrient System For Growing Marijuana in Soil

One of the easiest and simplest nutrient systems for beginning marijuana growers in soil

is Botanicare Pure Blend for soilBotanicare Pure Blend for soilBotanicare Pure Blend for soilBotanicare Pure Blend for soil....

I recommend Botanicare Pure Blend because this system is easy to use, cheap, and can be found

at almost any hydro store,

Plus Botanicare Pure Blend for Soil works great for growing marijuana, without needing a lot of

extra care, or any additiona supplements.

There are two different bottles that you will need to grow marijuana, "Grow" and "Bloom."

Just use "Grow" during the Vegetative stage and "Bloom" during the Flowering stage. It's super

simple.

Make sure you get the version for soil if growing in soil, because Botanicare offers Make sure you get the version for soil if growing in soil, because Botanicare offers Make sure you get the version for soil if growing in soil, because Botanicare offers Make sure you get the version for soil if growing in soil, because Botanicare offers aaaa

hydroponic version of the same nutrient line.hydroponic version of the same nutrient line.hydroponic version of the same nutrient line.hydroponic version of the same nutrient line.

Easy Nutrient System For Growing Marijuana with HydroponicsEasy Nutrient System For Growing Marijuana with HydroponicsEasy Nutrient System For Growing Marijuana with HydroponicsEasy Nutrient System For Growing Marijuana with Hydroponics

(coco coir, soilless growing medium, deep water culture, bubbleponics, and basically

everything besides soil)

A time-tested, simple nutrient system for growing marijuana hydroponically is the GeneralGeneralGeneralGeneral

Hydroponics TrioHydroponics TrioHydroponics TrioHydroponics Trio....

This complete nutrient system can be used in water, coco coir, or any growing medium besides

soil and works amazingly well for growing weed, without needing a lot of fuss.

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What are the best marijuana nutrients? | Grow Weed Easy http://www.growweedeasy.com/best-marijuana-nutrients-review

1 of 5 8/12/2013 11:56 PM

You don't need any other nutrients to grow marijuana hydroponically; this trio alone will give

your marijuana plants what they need to flourish through the vegetative and flowering stages.

I love growing with General Hydroponics Trio because I don't have to worry about nutrients and

can focus on creating a great growing environment and harvesting my fat buds.

Simply follow the included nutrient schedule included nutrient schedule included nutrient schedule included nutrient schedule (start at half strength and increase as needed)

and keep the pH of your water between 5.5-6.5 at the plant roots for best results.

More info on monitoring and adjusting the pH below...

With all nutrient systems, don't start it at full strength or it might burn your plants!

Different strains have different preferences, and many are very sensitive to nutrient burn.

Start at half-strength and only raise the amount if you notice that plants are showing signs of

not getting enough nutrients, such as growing pale green leaves.

How do I know if my marijuana plants are having nutrient problems?

IMPORTANT: Root pH Affects How Well Your Marijuana Aborbs Nutrients!IMPORTANT: Root pH Affects How Well Your Marijuana Aborbs Nutrients!IMPORTANT: Root pH Affects How Well Your Marijuana Aborbs Nutrients!IMPORTANT: Root pH Affects How Well Your Marijuana Aborbs Nutrients!

It's important to maintain the pH of your root environment to prevent nutrient problems.

The easiest way to do that is to test the pH of your water before you

water your plants.

Some growers get lucky and successfully grow weed without testing

the pH of their water, but most people who don't test for pH will start

seeing signs of nutrient deficiencies and other nutrient problems.

This is because even if the right amounts of nutrients are present, your weed simply cannot

absorb them if the pH isn't in the correct range.

It's actually really easy, quick, and cheap to learn how to check and adjust the pH of your water,

and there are "pH test kits" specifically made for this purpose.

After you get the hang of it, checking and adjusting the pH and will take you less than 5 minutes

each time you water your plants. And your results (monster yields with huge buds and healthy

plants) speak for themselves.

Soil Optimal pH: Soil Optimal pH: Soil Optimal pH: Soil Optimal pH: 6.0 - 7.0

Hydroponics Optimal pH: Hydroponics Optimal pH: Hydroponics Optimal pH: Hydroponics Optimal pH: 5.5 - 6.5

Getting the pH exactly right isn't nearly as important as checking regularly and making sure it

stays within these ranges.

Full tutorial of checking and adjusting your pH hereFull tutorial of checking and adjusting your pH hereFull tutorial of checking and adjusting your pH hereFull tutorial of checking and adjusting your pH here (with a video by me walking you

through the whole thing, so you can see how easy it is!): http://growweedeasy.com/how-do-

Submit


2 of 5 8/12/2013 11:56 PM

i-check-the-pH-of-my-water

More Marijuana Nutrient Picks for:More Marijuana Nutrient Picks for:More Marijuana Nutrient Picks for:More Marijuana Nutrient Picks for:

Growing in Soil:

Botanicare Pure Blend for Soil (Grow/Bloom) (or get the soil tri-pack with Liquid

Karma) <-- Recommended for Beginners

Fox Farms Nutrient Trio for Soil

Dyna-Gro (Grow, Bloom)

House & Garden Soil A + B

Growing in Coco Coir:

Fox Farms Nutrient Trio for Hydroponics <-- Recommended for Beginners

General Hydroponics Flora Series Nutrient Trio

Canna Coco A + B

Dyna-Gro (Grow, Bloom)

House & Garden Coco A + B

Botanicare Pure Blend for Hydro (Grow / Bloom) (or get the hydro tri-pack with Liquid

Karma)

Growing in Water (Marijuana Nutrients for all Hydroponic Applications including

Recirculating Systems):

General Hydroponics Flora Series Nutrient Trio <-- Recommended for Beginners

House & Garden Aqua Flakes A + B

Botanicare Pure Blend for Hydro (Grow / Bloom) (or get the hydro tri-pack with Liquid

Karma)

Best supplements:

Pro-tekt (silica, stronger branches/sturdier plants, better heat/cold resistance, more

resistant to mites)

Aquashield (banish root rot for good and promote root health, in our tests Aquashield

works better at getting rid of root rot than the 10x more expensive Great

White supplement)

***Note: Advanced NutrientsAdvanced NutrientsAdvanced NutrientsAdvanced Nutrients (Grow, Micro, Bloom) offers an expensive nutrient line which is

formulated for plants like marijuana, and many growers swear by it. It will definitely work for

growing marijuana, no question about it. However, in side-by-side comparisons, cheaper

nutrients systems often outperform Advanced Nutrients as far as marijuana yields. I've never

tried the Advanced Nutrients line due to the expensive price tag, especially since I've had such

great results with these other systems, but I felt the need to mention it because it's so often

used to grow marijuana. Here's the Advanced Nutrients calculator to figure out how much you'll

need to use: http://www.advancednutrients.com/hydroponics/calc/


3 of 5 8/12/2013 11:56 PM

With all nutrient systems that you're trying out for the first time, I highly suggest starting atI highly suggest starting atI highly suggest starting atI highly suggest starting at

half the recommended nutrient levels when growing weed.half the recommended nutrient levels when growing weed.half the recommended nutrient levels when growing weed.half the recommended nutrient levels when growing weed.

Only increase the concentration of nutrients if you see signs of nutrient deficiencieOnly increase the concentration of nutrients if you see signs of nutrient deficiencieOnly increase the concentration of nutrients if you see signs of nutrient deficiencieOnly increase the concentration of nutrients if you see signs of nutrient deficiencies.s.s.s.

This is because, for whatever reason, most nutrient recommendations are way too strong for

growing most strains of marijuana. (Maybe nutrient companies want to sell more by having you

use more?)

So if the included nutrient schedule say add a teaspoon to a gallon of water, I'd say you cut that

in half and add a ½ teaspoon to a gallon of water. If it says to add 2ml to a liter of water, than

you add 1ml to a liter of water.

I've found over and over that you get the best yields by erring on the side of "too little" over "too

much" nutrients. I always start a half strength and only move up when I see deficiencies.

For example, I do increase nutrient levels if I notice yellowing leaves towards bottom ofI do increase nutrient levels if I notice yellowing leaves towards bottom ofI do increase nutrient levels if I notice yellowing leaves towards bottom ofI do increase nutrient levels if I notice yellowing leaves towards bottom of

plant.plant.plant.plant.

Now yellowing leaves towards the bottom of your plant is okay if you're late in the flowering

stage, but this symptom needs to be corrected at any other time earlier in the plant's life (to

make sure you have enough leaves that last all the way to the end).

Wanna "steal" this article?

Here at GrowWeedEasy.com, we are dedicated to getting this information

into as many hands as possible. You are welcome to republish this entire

article as long as you do not edit, remove or or otherwise change any part

of it without permission.

Please don't hesitate to Contact GrowWeedEasy.com with any questions.

Happy growing!

TagsTagsTagsTags General Cannabis Care Beginner Nutrients


4 of 5 8/12/2013 11:56 PM

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Nutrient disorders are caused by too much or too little of one or several nutrients being available. These

nutrients are made available between a pH range of 5 and 7 and a total dissolved solids (TDS) range of

800 to 3000 PPM. Maintaining these conditions is the key to proper nutrient uptake.

-------------------------------------------------------------------------------- Nutrients Over twenty elements are needed

for a plant to grow. Carbon, hydrogen and oxygen are absorbed from the air and water. The rest of the

elements, called mineral nutrients, are dissolved in the nutrient solution. The primary or macro- nutrients

(nitrogen (N), phosphorus (P) and potassium (K)) are the elements plants use the most. Calcium (Ca) and

magnesium (Mg) are secondary nutrients and used in smaller amounts. Iron (Fe), sulfur (S), manganese

(Mn), boron (B), molybdenum (Mo), zinc (Zn) and copper (Cu) are micro-nutrients or trace elements. Trace

elements are found in most soils. Rockwool (hydroponic) fertilizers must contain these trace elements, as

they do not normally exist in sufficient quantities in rockwool or water. Other elements also play a part in

plant growth. Aluminum, chlorine, cobalt, iodine, selenium, silicon, sodium and vanadium are not normally

included in nutrient mixes. They are required in very minute amounts that are usually present as impurities

in the water supply or mixed along with other nutrients. *NOTE: The nutrients must be soluble (able to

be dissolved in water) and go into solution.

-------------------------------------------------------------------------------- Macro-nutrients Nitrogen (N) is primary to

plant growth. Plants convert nitrogen to make proteins essential to new cell growth. Nitrogen is mainly

responsible for leaf and stem growth as well as overall size and vigor. Nitrogen moves easily to active

young buds, shoots and leaves and slower to older leaves. Deficiency signs show first in older leaves.

They turn a pale yellow and may die. New growth becomes weak and spindly. An abundance of nitrogen will

cause soft, weak growth and even delay flower and fruit production if it is allowed to accumulate.

-------------------------------------------------------------------------------- Phosphorus (P) is necessary for

photosynthesis and works as a catalyst for energy transfer within the plant. Phosphorus helps build strong

roots and is vital for flower and seed production. Highest levels of phosphorus are used during germination,

seedling growth and flowering. Deficiencies will show in older leaves first. Leaves turn deep green on a

uniformly smaller, stunted plant. Leaves show brown or purple spots. NOTE: Phosphorus flocculates

when concentrated and combined with calcium.

-------------------------------------------------------------------------------- Potassium (K) activates the manufacture and

movement of sugars and starches, as well as growth by cell division. Potassium increases chlorophyll in

foliage and helps regulate stomata openings so plants make better use of light and air. Potassium

encourages strong root growth, water uptake and triggers enzymes that fight disease. Potassium is

necessary during all stages of growth. It is especially important in the development of fruit. Deficiency signs

of potassium are: plants are the tallest and appear healthy. Older leaves mottle and yellow between veins,

followed by whole leaves that turn dark yellow and die. Flower and fruit drop are common problems

associated with potassium deficiency. Potassium is usually locked out by high salinity.

-------------------------------------------------------------------------------- Secondary Nutrients Magnesium (Mg) is

found as a central atom in the chlorophyll molecule and is essential to the absorption of light energy.

Magnesium aids in the utilization of nutrients, neutralizes acids and toxic compounds produced by the plant.

Deficiency signs of magnesium are: Older leaves yellow from the center outward, while veins remain green

on deficient plants. Leaf tips and edges may discolor and curl upward. Growing tips turn lime green if the

deficiency progresses to the top of the plant.

-------------------------------------------------------------------------------- Calcium (Ca) is fundamental to cell

manufacture and growth. Soil gardeners use dolomite lime, which contains calcium and magnesium, to keep

the soil sweet or buffered. Rockwool gardeners use calcium to buffer excess nutrients. Calcium moves

slowly within the plant and tends to concentrate in roots and older growth. Consequently young growth

Cannabis Nutrient Disorders http://growinghelp.com/cannabis/nutrientdisorders_guide.php

2 of 8 8/9/2013 5:23 PM

shows deficiency signs first. Deficient leaf tips, edges and new growth will turn brown and die back. If too

much calcium is applied early in life, it will stunt growth as well. It will also flocculate when a concentrated

form is combined with potassium. --------------------------------------------------------------------------------

Trace Elements Sulphur (S) is a component of plant proteins and plays a role in root growth and chlorophyll

supply. Distributed relatively evenly with largest amounts in leaves which affects the flavor and odor in

many plants. Sulphur, like calcium, moves little within plant tissue and the first signs of a deficiency are pale

young leaves. Growth is slow but leaves tend to get brittle and stay narrower than normal.

-------------------------------------------------------------------------------- Iron (Fe) is a key catalyst in chlorophyll

production and is used in photosynthesis. A lack of iron turns leaves pale yellow or white while the veins

remain green. Iron is difficult for plants to absorb and moves slowly within the plant. Always use chelated

(immediately available to the plant) iron in nutrient mixes.

-------------------------------------------------------------------------------- Manganese (Mg) works with plant enzymes

to reduce nitrates before producing proteins. A lack of manganese turns young leaves a mottled yellow or

brown. -------------------------------------------------------------------------------- Zinc (Z) is a catalyst and

must be present in minute amounts for plant growth. A lack of zinc results in stunting, yellowing and curling

of small leaves. An excess of zinc is uncommon but very toxic and causes wilting or death.

--------------------------------------------------------------------------------

Copper (C) is a catalyst for several enzymes. A shortage of copper makes new growth wilt and

causes irregular growth. Excesses of copper causes sudden death. Copper is also used as a fungicide and

wards off insects and diseases because of this property.

--------------------------------------------------------------------------------

Boron (B) is necessary for cells to divide and protein formation. It also plays an active role in

pollination and seed production.

--------------------------------------------------------------------------------

Molybdenum (Mn) helps form proteins and aids the plant's ability to fix nitrogen from the air. A

deficiency causes leaves to turn pale and fringes to appear scorched. Irregular leaf growth may also result.

--------------------------------------------------------------------------------

These nutrients are mixed together to form a complete plant fertilizer. The mix contains all the

nutrients in the proper ratios to give plants all they need for lush, rapid growth. The fertilizer is

dissolved in water to make a nutrient solution. Water transports these soluble nutrients into contact with

the plant roots. In the presence of oxygen and water, the nutrients are absorbed through the root hairs.

-------------------------------------------------------------------------------- The above text is excerpted from

George Van Pattens' excellent book "Gardening: The Rockwool Book".

Key on Nutrient Disorders

To use the Problem-Solver, simply start at #1 below. When you think you've found the problem, read the

Nutrients section to learn more about it. Diagnose carefully before

making major changes.


3 of 8 8/9/2013 5:23 PM

1) a) If the problem affects only the bottom or middle of the plant go to #2.

b) If it affects only the top of the plant or the growing tips, skip to #10. If the problem seems to affect the

entire plant equally, skip to #6.

2) a) Leaves are a uniform yellow or light green; leaves die & drop; growth is slow. Leaf margins are not

curled-up noticeably. >> Nitrogen (N) deficiency.

b) If not, go to #3.

3) a) Margins of the leaves are turned up, and the tips may be twisted. Leaves are yellowing (and may

turn brown), but the veins remain somewhat green. >> Magnesium (Mg) deficiency.


4) a) Leaves are browning or yellowing. Yellow, brown, or necrotic (dead) patches, especially around the

edges of the leaf, which may be curled. Plant may be too tall. >> Potassium (K) deficiency.

b) If not, keep reading…

5) a) Leaves are dark green or red/purple. Stems and petioles may have purple & red on them. Leaves

may turn yellow or curl under. Leaf may drop easily. Growth may be slow and

leaves may be small. >> Phosphorous (P) deficiency.


6) a) Tips of leaves are yellow, brown, or dead. Plant otherwise looks healthy & green. Stems may be

soft >> Over-fertilization (especially N), over-watering, damaged roots, or

insufficient soil aeration (use more sand or perlite. Occasionally due to not enough N, P, or K.


7) a) Leaves are curled under like a ram's horn, and are dark green, gray,

brown, or gold. >> Over-fertilization (too much N).

b) If not, go to #8…

8) a) The plant is wilted, even though the soil is moist. >>Over-fertilization, soggy soil, damaged roots,

disease; copper deficiency (very unlikely).


9) a) Plants won't flower, even though they get 12 hours of darkness for over 2 weeks. >> The night

period is not completely dark. Too much nitrogen. Too much pruning or cloning.

b) If not, go to #10...

10) a) Leaves are yellow or white, but the veins are mostly green. >> Iron (Fe) deficiency.

b) If not, #11.

11) a) Leaves are light green or yellow beginning at the base, while the leaf

margins remain green. Necrotic spots may be between veins. Leaves are not twisted. >> Manganese (Mn)

deficiency.

b) If not, #12.

12) a) Leaves are twisted. Otherwise, pretty much like #11. >> Zinc (Zn)

deficiency.

b) If not, #13.


4 of 8 8/9/2013 5:23 PM

13) a) Leaves twist, then turn brown or die. >> The lights are too close to the plant. Rarely, a Calcium

(Ca) or Boron (B) deficiency.

b) If not… You may just have a weak plant.

Solutions to Nutrient Deficiencies

The Nutrients: Nitrogen - Plants need lots of N during vegging, but it's easy to overdo it. Added too much?

Flush the soil with plain water. Soluble nitrogen (especially nitrate) is the form that's the most quickly

available to the roots, while insoluble N (like urea) first needs to be broken down by microbes in the soil

before the roots can absorb it. Avoid excessive ammonium nitrogen, which can interfere with other

nutrients. Too much N delays flowering. Plants should be allowed to become N-deficient late in flowering for

best flavor. Magnesium - Mg-deficiency is pretty common since cannabis uses lots of it and many

fertilizers don't have enough of it. Mg-deficiency is easily fixed with ¼ teaspoon/gallon of Epsom salts (first

powdered and dissolved in some hot water) or foliar feed at ½ teaspoon/quart. When mixing up soil, use 2

teaspoon dolomite lime per gallon of soil for Mg. Mg can get locked-up by too much Ca, Cl or ammonium

nitrogen. Don't overdo Mg or you'll lock up other nutrients. Potassium - Too much sodium (Na) displaces

K, causing a K deficiency. Sources of high salinity are: baking soda (sodium bicarbonate "pH-up"), too

much manure, and the use of water-softening filters (which should not be used). If the problem is Na, flush

the soil. K can get locked up from too much Ca or ammonium nitrogen, and possibly cold weather.

Phosphorous - Some deficiency during flowering is normal, but too much shouldn't be tolerated. Red

petioles and stems are a normal, genetic characteristic for many varieties, plus it can also be a

co-symptom of N, K, and Mg-deficiencies, so red stems are not a foolproof sign of P-deficiency. Too much

P can lead to iron deficiency. Iron - Fe is unavailable to plants when the pH of the water or soil is too

high. If deficient, lower the pH to about 6.5 (for rockwool, about 5.7), and check that you're not adding too

much P, which can lock up Fe. Use iron that's chelated for maximum availability. Read your fertilizer's

ingredients - chelated iron might read something like "iron EDTA". To much Fe without adding enough P can

cause a P-deficiency.

Manganese - Mn gets locked out when the pH is too high, and when there's too much iron. Use

chelated Mn.

Zinc - Also gets locked out due to high pH. Zn, Fe, and Mn deficiencies often occur together, and are

usually from a high pH. Don't overdo the micro-nutrients- lower the pH if that's the problem so the

nutrients become available. Foliar feed if the plant looks real bad. Use chelated zinc.

Check Your Water - Crusty faucets and shower heads mean your water is

"hard," usually due to too

many minerals. Tap water with a TDS (total dissolved solids) level of more

than around 200ppm (parts

per million) is "hard" and should be looked into, especially if your plants

have a chronic problem. Ask

your water company for an analysis listing, which will usually list the pH,

TDS, and mineral levels (as

well as the pollutants, carcinogens, etc) for the tap water in your area.

This is a common request,

especially in this day and age, so it shouldn't raise an eyebrow. Regular


5 of 8 8/9/2013 5:23 PM

water filters will not reduce a

high TDS level, but the costlier reverse-osmosis units, distillers, and

de-ionizers will. A digital TDS

meter (or EC = electrical conductivity meter) is an incredibly useful tool

for monitoring the nutrient

levels of nutrient solution, and will pay for itself before you know it.

They run about $40 and up.

General Feeding Tips - Pot plants are very adaptable, but a general rule of

thumb is to use more

nitrogen & less phosphorous during the vegetative period, and the exact

opposite during the flowering

period. For the veg. period try a N:P:K ratio of about 10:7:8 (which of

course is the same ratio as

20:14:16), and for flowering plants, 4:8:8. Check the pH after adding

nutrients. If you use a reservoir,

keep it circulating and change it every 2 weeks. A general guideline for

TDS levels is as follows:

seedlings = 50-150 ppm; unrooted clones = 100-350 ppm; small plants =

400-800 ppm; large plants =

900-1800 ppm; last week of flowering = taper off to plain water. These

numbers are just a guideline, and

many factors can change the actual level the plants will need. Certain

nutrients are "invisible" to TDS

meters, especially organics, so use TDS level only as an estimate of actual

nutrient levels. When in

doubt about a new fertilizer, follow the fertilizer's directions for

feeding tomatoes. Grow a few tomato or

radish plants nearby for comparison.

PH - The pH of water after adding any nutrients should be around 5.9-6.5

(in rockwool, 5.5-6.1) .

Generally speaking, the micro-nutrients (Fe, Zn, Mn, Cu) get locked out at

a high pH (alkaline) above

7.0, while the major nutrients (N, P, K, Mg) can be less available in

acidic soil or water (below 5.0). Tap

water is often too alkaline. Soils with lots of peat or other organic

matter in them tend to get too acidic,

which some dolomite lime will help fix. Soil test kits vary in accuracy,

and generally the more you pay

the better the accuracy. For the water, color-based pH test kits from

aquarium stores are inexpensive,

but inaccurate. Invest in a digital pH meter ($40-80), preferably a

waterproof one. You won't regret it.

Other Things…

Cold - Cold weather (below 50F/10C) can lock up phosphorous. Some


6 of 8 8/9/2013 5:23 PM

varieties, like equatorial sativas,

don't take well to cold weather. If you can keep the roots warmer, the

plant will be able to take cooler

temps than it otherwise could.

Heat - If the lights are too close to the plant, the tops may be curled,

dry, and look burnt, mimicking a

nutrient problem. Your hand should not feel hot after a minute when you

hold it at the top of the plants.

Raise the lights and/or aim a fan at the hot zone. Room temps should be

kept under 85F (29C) -- or 90F

(33) if you add additional CO2.

Humidity - Thin, shriveled leaves can be from low humidity. 40-80 % is

usually fine.

Mold and fungus - Dark patchy areas on leaves and buds can be mold. Lower

the humidity and

increase the ventilation if mold is a problem. Remove any dead leaves,

wherever they are. Keep your

garden clean.

Insects - White spots on the tops of leaves can mean spider mites

underneath.

Sprays - Foliar sprays can have a "magnifying glass" effect under bright

lights, causing small white,

yellow or burnt spots which can be confused with a nutrient problem. Some

sprays can also cause

chemical reactions.

Insufficient light -- tall, stretching plants are usually from using the

wrong kind of light.. Don't use

regular incandescent bulbs ("grow bulbs") or halogens to grow cannabis.

Invest in fluorescent lighting

(good) or HID lighting (much better) which supply the high-intensity light

that cannabis needs for

good growth and tight buds. Even better, grow in sunlight.

Clones - yellowing leaves on unrooted clones can be from too much light, or

the stem may not be firmly

touching the rooting medium. Turn off any CO2 until they root. Too much

fertilizer can shrivel or wilt

clones - plain tap water is fine.

CANNABIS NUTRITIENS


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Nutrient Problems Guide

You will seldom have a deficiency with Mandala strains if you use:

quality horticultural potting soil

a sufficient container size

control the pH of your water for soil (should be 6.2-6.5)

monitor the EC and pH of your hydroponic system regularly

Mandala strains are bred for an easy and uncomplicated grow and are very nutrient efficient in soil. But they also growfast and vigorously and need the space and soil quality to support this healthy development.

Giving your plants natural nutrients in the form of good soil and a small dosages of fertilizing (10-15% of recommendedstrength for mineral based fertilizers and indoor never above EC 0.7 mS/cm) after 4-5 weeks of growth to top up used nutrientsis usually sufficient for great development and high yields. To achieve this you only have to prevent rootbound plants bychoosing the correct container size and repotting on time into fresh quality soil. Indoor our varieties can even grow on soilwithout any extra fertilizing!

Be sensible...big containers provide a lot of nutrients, small containers will last only for a few weeks. Don't make themistake to force your fast growing Mandala's into tiny pots.

Nutrient availability is directly proportional to container size. Make sure you transplant on time and into a decently sizedcontainer (at least 4-5 Liters/1 gallon for early growth). Our strains are remarkably vigorous and tough - don’t be afraid ofhandling them and repotting a few times if necessary. They will thank you for the extra nutrients and root space!

If you are growing outdoor in containers please use at least 10-15L/2-3 gallon pots for the grow phase till first signs offlowering. Small pots quickly lead to symptoms of underfeeding and can also trigger a high ratio of male plants due to nutrientdeficiency and cramped root space. Adjust the container size according to the size of your plants and repot when they becomerootbound. For more info on recommended container sizes read our SOIL GUIDE & FAQ.

Fertilizing on soil is always the worse choice compared to fresh soil and sufficient root space! Don't be tempted tobelieve that a lot of fertilizing will give you better results. This is a myth from the agrochemical industry that wants tosell their products in huge quantities. Our environment is already suffering worldwide from the results.

Fertilizer should be used with extreme care indoor and seen only as a minor supplement to top up nutrients or to assist incases of accidental deficiencies. In hydroponics moderate EC levels should be used instead of heroic dosages to "force"flowering. For outdoor the fertilizing must be dosaged in accordance with soil quality and the size of the plants.

Choosing Soil

We recommend brands such as Klassman KT2, FoxFarm Ocean Forest, Pindstrup Universal, CompoSana Universal/Flower/Bio orPlantacion (Spain), CANNA Professional, FloraGard Vital Blumenerde or comparable FloraGard soil mixes for flowers/plants.Use a seedling mix for germinating your seeds. Further details in our SOIL GUIDE.

Worm manure and compost is a valuable additive (use 15-20% in your mix). In European grow shops you can purchase a qualitysoil product imported from Holland called CANNA Professional. We do not recommend the soil products from Bio Bizz andPlagron.

Heavily fertilized soils like Bio Bizz All-Mix have shown not to be suitable for indoor grows. They contain too much nitrogen,have an extremely high EC (salt) level, and are better used for outdoor where the plants have a longer growth period.The LightMix offered by Plagron and Bio Bizz is extremely low in nutrients and completely unsuitable for any natural soil cultivation.

Good soil for cannabis cultivation has the following formula:

Compo Sana Universal

Marijuana Nutrient Problems http://www.mandalaseeds.com/Guides/Marijuana-Nutrient-Problems

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pH 5.5-6.5

N:200-450 mg/L

P:200-400 mg/L

K:300-500 mg/L

Common Mistakes

With quality horticultural grade soil you do not need to mix additional perlite. This is a completely outdated practice from 30+years ago when there was a much smaller selection of horticultural potting soil available for non-commercial gardeners.Nowadays all quality horticultural grade soil for flowering or potted plants is manufactured with a perfect air-to-water ratio.

Do not use sand, coco fibre, or hydro correls in your potting mix. These materials do not contain any nutrients, which canlead to a deficiency in pots when plants grow larger.

Hydro correls change the pH of the soil (it becomes more alkaline with pH 7-8).

Growers mixing potting soil with considerable amounts of coco coir can end up with a large percentage of male plants.

Nutrient deficiencies and nutrient overabundance (ie. up to the point of serious overfertilizing) can both cause seriouschanges in the pH and salt levels of the growing medium. This affects biochemical changes in the plants during sexing orpre-flowering and can increase the ratio of male plants or trigger the appearance of male flowers on females.

Nutrient Problems

Nitrogen Deficiency

Cannabis is a fast growing plant species and requires generous amounts ofnitrogen throughout growth and early flowering. Nitrogen is regarded as belongingto the group of three primary nutrients essential for plant growth. The other twonutrients in this group are phosphorus and potassium. These will be dealt withhere separately. Nitrogen is stored mainly in the leaves and shoot tips, which iswhy it is inadvisable to remove healthy leaves on plants, as these are the "storagehouse" for important nutrients. The production of enzymes, proteins, chlorophylland other vital ingredients for healthy development are all dependent onnitrogen. Chlorophyll lends plants their green color which is why yellowing leavesare a telltale sign of N deficiency.

Causes:

A serious pest infestation of aphids, white flies, or spider mites that suck out theleaves leads to deficiency symptoms.

Too small container size for adult plants is one of the most common mistakes incannabis growing. Especially in light intensive situations such as balcony orgarden grows the plants will quickly yellow and wilt. Don't be too lazy and repotyour plants. You can do this up to the third week of flowering even.

Poor soil quality. The second major cause for a deficiency. The importance ofusing quality grade horticultural soil cannot be stressed enough. Do not usetopsoil from the forest if you are not certain about it's nitrogen content.

Decomposed leaf material contains no nitrogen (obviously since these are the yellowed leaves shed by the trees!) and makesup for a large percentage of forest topsoil. Also loamy and sandy soil are mainly devoid of important nutrients. If you do utilizesuch soil in guerilla grows, etc. then make sure to supplement it with long term acting fertilizer, or enrich it with a mix oforganic nutrients (bat guano, composted soil, etc.) that have sufficient quantities of nitrogen to support plant growth.

A pH imbalance will block nutrient uptake in the root zone. Make sure that you keep the pH within the acceptable range forsoil or hydroponics.

Lack of fertilizing. A minimum of fertilizing on soil is usually necessary to boost plant growth, since cannabis tends to growfaster than the roots can assimilate the natural nutrients in soil. In low light situations or indoors this is less of an issue than ina greenhouse/outdoors/or in a setup using CO2. With high quality soil and a good container size you can probably do withoutany grow fertilizer if you are cultivating short to medium sized plants.

Symptoms:

The lower leaves yellow between the veins until the entire leaf is eventually yellow. It wilts and dies.

The symptoms spread upwards affecting all sun leaves and then the smaller and younger leaves as well.


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Plant growth is inhibited. The plants remain short and underdeveloped if nitrogen deficiency is severe in the growth phase.

During flowering early deficiency can lead to a significant decrease in yield. Plants that are in the last 3 weeks of flowering donot require nitrogen if they have remained reasonably healthy up to that point. A yellowing and shedding of leaves during thefinal weeks of flowering is quite natural among otherwise healthy plants and should not be held up by heroic dosages ofnitrogen (which would result in many undesirable complications such as: mold, sudden stop in bud development, dying ofpistils, over-fertilization, rejuvenation/leaf growth in buds).

Appearance of male flowers on female plants.

Phosphorus Deficiency

Growers are nowadays so obsessed with yield that a P deficiency has become lesscommon. The market is overflowing with products that supposedly increase budproduction. These chemical cocktails and organic wonder mixes are made withhigh levels of phosphorus. The trend to pump the plants full of a variety of "budboosters", often at extremely high dosages (ie. EC levels), is generally of moreconcern than combating deficiency symptoms! The good news is that cannabis canstore large amount of P in it's shoot and root tips and in the vascular tissue. Butstill, one should tread the middle path, as with all plant nutrients, and notoverfeed the plants.

Phosphorus is required during all stages of plant development – especially duringpronounced root and bud growth. It is necessary for photosynthesis and is acomponent of enzymes and proteins.

Causes:

Poor soil quality lacking sufficient amounts of phosphorus; loamy or waterloggedsoil.

A pH imbalance will block nutrient uptake in the root zone. Make sure that youkeep the pH within the acceptable range for soil or hydroponics (between 5.8 and6.8).

Lack of fertilizing. A minimum of fertilizing on soil is usually necessary to boostplant growth, since cannabis tends to grow faster than the roots can assimilate

the natural nutrients in soil. During flowering the phosphorus stored in the plant is gradually used up. Low to medium rangedosages of a quality grade fertilizer are sufficient to prevent any serious P deficiency in the peak period of flowering if youcultivating on soil. In hydroponics the plants have a steady supply of readily available nutrients, so it is not necessary toincrease EC levels and "force" plants to produce more buds. This can backfire and lead to over-fertilization with all it'saccompanying problems. If you do want to give your plants more P without raising the EC level, then consider adding osmosiswater to your tap water to lower the starting EC level. This way you can add some more fertilizer without affecting the regularEC level of the nutrient solution.

Over-fertilization. Too many salts in your medium will cause phosphate to become chemically bound and unavailable to theplants. In hydroponics you can flush the system. But in soil grows this is more of a problem since you will wash out importantnutrients and cause the soil to become waterlogged.

Symptoms:

In young plants a deficiency slows growth. The plants are underdeveloped with a poor root zone and small bluish-green leaves.

In flowering plants the leaves turn reddish-purple. This generally starts at the leaf tips and spreads towards the leaf stem.Stems may also redden. In acute cases leaves turn necrotic and fall off.

Bud growth and yield will be below average if a deficiency sets in during early to mid-flowering.

Seeded plants will have less well developed seeds.

Lack of vigor and overall lack of mold and pest resistance.

Potassium Deficiency

This mineral is the third in the group of primarynutrients required in larger quantities bycannabis. Potassium should be availablethroughout the plants life cycle. It plays a part inregulating transpiration, the manufacture ofstarches, sugars and chlorophyll. Potassium is


3 of 7 8/13/2013 8:54 AM

therefore important for the generation of energywithin the plant and enhances plant and rootgrowth. All complete fertilizers containpotassium. Kelp or seaweed extracts andcomposted soil such as worm castings is anexcellent organic source. Wood ash contains highlevels of potassium but due to the equally highcalcium content it also raises the pH and shouldonly be used on acidic soil.

Causes:

Poor soil quality.

Over-fertilization. Also here the same principlesapply as with phosphorus.

Symptoms:

A potassium deficiency sometimes resembles lack of nitrogen in the first stages of leaf deterioration. But the difference is thatthe leaves also develop rust-colored spots. Eventually the affected leaves wilt and drop.

The leaf tips on healthy leaves may turn brown and resemble the symptoms of over-fertilization. This is due to a disruption intranspiration (since potassium regulates the opening and closing of the stomata on the leaf surface, where water evaporatesfrom the plant and gases such as CO2 are drawn in).

In severe cases the stems become brittle.

A deficiency is more common in older plants and therefore the flowering phase will be negatively affected. You can expect lowyields.

Magnesium Deficiency

Magnesium is the fourth most important nutrientand used in larger amounts by cannabis plants. Itis also one of the more common deficienciesindoors, due to several factors that can occurwhich inhibit the uptake or availability ofMagnesium. Growers can act preventively byadding dolomite lime to the soil mix orwatering/spraying their plants with a solution ofEpsom salts. If you have vigorous plants andquality horticultural grade soil with a good pHvalue (6.0-7.0), then it is unlikely that you willget any Magnesium deficiency in your plants. Alsohydroponic setup's seldom experience Mgdeficiency since complete NPK fertilizers offer asufficient supply of this mineral.

Causes:

Acidic soil (pH 5.0-5.8).

Cold and water-logged/soggy soil.

Over-fertilization (nutrient blockage especially from high amounts of nitrate, potassium, and calcium).

"Hard" water with high calcium content can bind Magnesium in the soil (mix your tap water with osmosis water).


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Symptoms:

First indications resemble nitrogen deficiency: the lower to middle leaves yellow between the veins until the entire leaves areeventually yellow.

Rusty spots appear dotted throughout the leaves which distinguishes Mg deficiency from lack of nitrogen.

The leaf edges appear necrotic and curl up.

Some leaves develop a whitish tinge.

Symptoms spread throughout the plant by chronic deficiency.

Over-fertilization

Over-fertilization is a very common phenomenon in cannabis gardens and the #1 bud killer. We see more damage to floweringand yield through overfeeding than through any other gardening error. One of the main reasons is that the recommendeddosages on fertilizers are way too high for the normal uptake of plants. Also growers fail to judge what the true plantrequirements are during the grow and can be overzealous in wanting to make their plants grow bigger or better. Most peoplehave fallen prey to the marketing of the agrochemical industry and believe that they need a cupboard full of bottles to growsuccessfully. The problem is enhanced by the low quality of cannabis genetics on the commercial market as many strains aretoo weak to grow vigorously by themselves and conditioned to respond to artificial feeding.

Generally speaking it is important to provide your Mandala seedlings/clones with good quality soil and a sufficient containersize. This basically takes care of most or all of the nutrient requirements throughout the first 4+ weeks of growth. After thisperiod you should start 12/12 and then repot your females into fresh soil. Bigger containers must be provided if you extend thevegetative time (to raise mother plants for example).

Plants with good genetics are also not dependent on being "force fed". They develop a good root system and take care of theirown needs, as long as they can find what they are looking for in the substrate. Mandala strains belong to this category sincethey have hybrid vigour and develop very strong shoots, leaves, and root growth. All Mandala strains can be grown indoorwithout fertilizing (or just minimal feedings) from start to finish if you provide good soil and the correct container size.Fertilize only if you cannot repot on time into fresh soil, if you notice slight deficiency (usually mild nitrogen deficiency showsup after several weeks growth) and need to top up nutrients, or have run into more visible deficiency problems. Large motherplants usually require moderate periodic feedings.

Non-Mandala plants with poor genetics (ie. from too much inbreeding, etc.) will be difficult to handle either way and arefinicky: some require higher levels of feeding in hydroponics because they are so inefficient in nutrient uptake; others developa salt buildup very quickly because they are underdeveloped, weak, and cannot support fast growth.

Check the EC levels of your nutrient solution first and remember that regardless of what is written on the packaging – neverfeed your plants with more than EC 0.6-0.8 mS/cm (indoor) to 1.0-1.2 mS/cm (outdoor) on soil! This way you will always be onthe safe side. For hydroponics consider using lower EC levels (1.0-1.6 mS/cm) and flushing less, instead of heroic dosages thatalways push the plants to the edge. This is not only more environmentally friendly, healthier, but also means less stress andmaintenance problems.

Wait until your plants show slight deficiency symptoms like lack of leaf luster or a slight yellowing of the lowest leaves. Thereis no point in fertilizing a healthy plant that is lush and green. Why interfere in what nature does best?

When you fertilize give the plants time to assimilate the nutrients and use them for growth. Don't feed them every day orseveral times a week. Usually it takes 6-8 days for cannabis plants to fully show the effect of the fertilization if they aregrowing on soil. After this period of time you can make an assessment if they require a bit more or not. Cannabis grows best ifit is fertilized in small portions rather than receiving a big dosage all at once.

(Note: all EC levels indicated are from the Hanna Sharp EC meter and measured in milliSiemens)

Causes:

Planting young or flowering plants into a soil mix with high levels of nitrogen.

Failing to check the EC level of your nutrient solution in soil cultivation. If you don't check the EC level you have no idea howhigh the salt concentration is that you are feeding. The EC is also influenced to a large extent by the quality of your tapwater. It makes a big difference if you have tap water with an EC of 0.4 or 0.8 mS/cm. Depending on the water you thereforehave to adjust the dosage of the fertilizer, so that the nutrient solution does not exceed a certain max. EC level. If the waterquality is poor then you should use a household osmosis unit and mix the osmosis water approx. 50/50 with your regularwater to reach a low EC starting level.

Using the full recommended dosage of manufacturers instead of a minimal dosage to test plant response, and to see howmany nutrients are really required for healthy growth.

Fertilizing too often, such as weekly or even more frequently, which causes a build up of salts in the soil. Also the amountyou water influences how many salts the substrate/soil soaks up. Never feed your plants on dry soil.

Starting the feeding cycle too early for young plants, or feeding your plants although they show no signs of lacking any


5 of 7 8/13/2013 8:54 AM

essential nutrients.

Not topping off your hydroponic reservoir with fresh water when required.

Working with high EC levels in hydroponics to force growth/flowering, instead of using low to mid-range EC levels and flushingless.

Using the wrong pH/EC value of your water/nutrient solution which can block the uptake of mineral salts – thereby causing areverse osmotic effect in the substrate. The high levels of salt pull water out of the root system of your plants. This is whyover-fertilization dries up your plants.

Symptoms:

The symptoms are quite diverse and many are often mistaken as a nutrient deficiency! This is due to a lack of gardeningexperience on the part of the grower, and also due to misguided information in some internet sites where uneducated tipsabound.

In many cases over-fertilization is particularly caused by an excess of nitrogen. During the growth and pre-floral phase nitrogentoxicity is quite common. Growers tend to water with a complete fertilizer recommended for this phase and these products allcontain a medium to high levels of nitrogen. Nitrogen toxicity begins to show through excessive stem elongation and softtissue. The plants may appear healthy with lush growth until the negative effects start to set in. In flowering plants it can slowdown flowering or even bring it to a standstill. Flowering plants may rejuvenate. Most develop leafy buds and an unusually highamount of secondary shoots (depends on cannabis variety) if nitrogen levels are too high during the pre-flowering. The moreadvanced stages of excess nitrogen are accompanied by necrosis on many leaves. First the leaf tips burn and dry up. Rustybrown spots appear between the veins and eventually the entire leaf turns brown and falls off.

Bud development is halted and pistils die off suddenly as if they were pollinated.

Leaf edges curl up (similar to when plants have a "heat stroke") due to a disruption in their transpiration which cools downthe leaf surface. This symptom is especially pronounced in the upper part of the plant close to the light source.

Leaves discolor and quickly drop off. Some may yellow and wilt beforehand.

Diverse symptoms appear all at once signaling a multi-nutrient blockage - mainly due to excess salts from macro nutrients(nitrogen, phosphate and potassium).

Poor root development and stunted growth.

Plants become susceptible to mold due to a weakened immune system and bloated cell tissue that retains more water(especially with excess of nitrogen). High EC levels are one of the most common causes for Botrytis or grey mold.

Wilting of seedlings, freshly rooted clones, or young plants. Symptoms resemble lack of watering.

High male ratio or appearance of male flowers on female plants.

Bud mold (Botrytis) on flowering plants.

For photos and more details consult our FERTLIZING SMART GUIDE.

Multi-Nutrient Blockage

In this photograph you can see the diverse symptoms of a multi-nutrient blockage.It arises when excess salts in the substrate bind secondary nutrients such asmagnesium, iron, zinc, manganese, calcium, manganese and copper. Usuallyover-fertilizing with potassium and phosphorus, present in high amounts infertilizers used for blooming such as the potent 13-14 PK products, causes such anutrient blockage. The leaves develop a checkered appearance of yellow, brown,and white spots with necrotic edges and sometimes also inter-veinal chlorosis(yellowing). Sometimes weak plants or poor genetics are partly to blame.

Symptoms can spread throughout the plant stunting growth and bud development.In such cases the substrate should be flushed thoroughly. Monitor the EC value ofthe excess water leaching out of the substrate. Continue flushing until it reachesan acceptable level. In soil this is always a difficult situation since you don't wantto complicate matters by water-logging the soil. Flowering plants in the advancedstages of bud development may develop mold if they stand too long in soggy soil.If harvest is near you should simply stop fertilizing and live with the results. Youngplants can be flushed more easily and you can also plant them in fresh soil andlarger pots to let them recuperate naturally.


6 of 7 8/13/2013 8:54 AM

Learn how to fertilize wisely and

when. Essential reading to keep

your plants and harvest safe!

Fertilizing Guide

Nutrients, water and pH are vital

to cannabis cultivation. This easy

to understand intro covers all

topics.Water & pH

What you need to know about

growing in soil, how to buy the

best soil product, organic

additives, etc.Soil Guide

DisclaimerContact

© All rights reserved, Mandala Seeds Ltd. 2004 - 2012.

The complete design of this web site and all its contents and single components such as images, logo, text, etc. belong to Mandala Seeds. No unauthorized

copying, distribution, hiring and/or lending of our web pages or their contents is permitted without our written consent.


7 of 7 8/13/2013 8:54 AM

1. Why Use These Expensive Meters?

2. How To Use Them

2.General Tips

Is the yield of your plants not as large as expected? Do your plants often display "burnt"

symptoms of over fertilization?

The solution might be to start using pH and EC meters.

1. Why Use pH and EC Meters?

A pH meter measures the acidity of the water on a scale from zero to 14. This scale is not a linear scale,

but an exponential scale. This means that the difference between a pH of six and a pH of seven is gigantic.

When the pH is too high or too low, the roots cannot take up the nutrients in the proper proportions.

Generally, this will show up in the plant as deficiencies of one nutrient or another, and as burnt leaf tips,

caused by overfertilization of one nutrient. The result is that growth will slow, the yield will be low, and

ultimately, the plant may die.

One remedy is to give the plants fewer nutrients, but then they are certain to develop even more

deficiencies, and the yield will not be as good as it can be. When the pH is just right, it is unlikely that

deficiencies will occur. The plant will be able to take up the nutrients in the correct proportions and

overfertilization will be a thing of the past.

In other words: with the wrong pH, half the recommended nutrients will cause overfertilization. With the right

pH, the full recommended dose will make for healthy and strong plants.

An EC meter measures the electrical conductivity of the water. Clean water has a low EC. When you add

nutrients and pH adjusters, the EC will go up. You can use this for measuring how many nutrients can put in

the water without causing overfertilization.

It can be hard sometimes to eyeball the required amount of nutrients. Sometimes, you're not quite sure how

big your container water is or you have no means of measuring the nutrients accurately. Even if all these

things are no problem, it is still possible that the recommended dosage of nutrients as printed on the label is

too low for your plants, and your plants would benefit from a higher dose. Using an EC meter together with

a pH meter, you can measure the optimum dose for your plants without causing overfertilization.

2. How To Use pH and EC Meters

Growing in soil

The pH should be 6.4 when you sprout the seeds or plant the clones. As the weeks go by, slowly lower the

pH until it is 6.0 during the last month of flowering. This will allow the plants to take up fewer nutrients when

they are little and more nutrients when they are growing and flowering.

Similarly, the EC should be 1.0 when you sprout the seeds or plant the clones. Slowly raise the EC to 2.0

for the last four weeks of flowering.

Troubleshooting cannabis growing health problems. http://growinghelp.com/cannabis/ph_ec_meters_guide.php

2 of 3 8/9/2013 5:08 PM

3. General Tips

The pH can be lowered by using vinegar, or you can buy special pH Down from the bigger garden supply

stores. These stores will also sell pH Up.

Adjusting the pH can be maddening sometimes, because the scale is exponential. In practical terms, this

means that you have to lower the pH or raise the pH by adding very small amounts of adjusters. If your pH

is too high, and you add too much pH Down, you have to add pH Up. This can go on for while, and then

your EC might be too high.

Recalibrate the pH and EC meters about once a month. Some meters need a special storage solution for

the sensor. Please be sure to buy this storage solution as well, it will make the difference between a

well-working meter and a useless meter. Do not use the EC meter without also measuring and adjusting the

pH. If you use the EC meter only, you almost certainly kill your plants by over fertilization. You can,

however, use a pH meter without an EC meter as long as you don't add more nutrients than recommended

on the label of the nutrients bottle. Recommendations for using pH and EC meters with hydroponics will be

added later.

How to use a PH meter?

Troubleshooting cannabis growing health problems. http://growinghelp.com/cannabis/ph_ec_meters_guide.php

3 of 3 8/9/2013 5:08 PM

growinghelp.com http://growinghelp.com/weed/ph_and_fertilizers.php

PH AND FERTILIZERS - Weed Growing Guide

BUY SEEDS

Growing Help - How to Grow Weed?

PH can make or break your nutrient solution. 6.7-6.2 is best to ensure there is no nutrient lock-up occurring.

Hydroponics requires the solution to be PH corrected for the medium before exposing to the plants.

Phosphoresic acid can make the PH go down; lime or potash can take it up when it gets too acid. Buy a PH

meter for $10 and use it in soil, water, and hydroponic medium to make sure your not going alkaline or acid over

time. Most neutral mediums can use a little vinegar to make them just this side of 7 ph to 6.5 or so.

Most fertilizers cause a ph change in the soil. Adding fertilizer to the soil almost always results in a more acidic

ph.

As time goes on, the amount of salts produced by the breakdown of fertilizers in the soil causes the soil to

become increasingly acidic and eventually the concentration of these salts in the soil will stunt the plant and

cause browning out of the foliage. Also, as the plant gets older its roots become less effective in bringing food

to the leaves. To avoid the accumulation of these salts in your soil and to ensure that your plant is getting all of

the food it needs you can begin leaf feeding your plant at the age of about 1.5 months. Dissolve the fertilizer in

worm water and spray the mixture directly onto the foliage. The leaves absorb the fertilizer into their veins. If

you want to continue to put fertilizer into the soil as well as leaf feeding, be sure not to overdose your plants.

PH AND FERTILIZERS - Weed Growing Guide http://growinghelp.com/weed/ph_and_fertilizers.php

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Breeding Weed

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Managing pH in my cannabis grow: Howto check and adjust the pH of water

The pH of your marijuana plant's root zone is very important to

preventing nutrient problems with growing marijuana. This is because

when the pH is too high or too low, the plant's roots will not be able to

absorb nutrients properly.

As a result of the pH being too high or too low, cannabis plants may start

showing signs of nutrition deficiencies even if the nutrients are available

in the growing medium.

Yes, that's worth repeating. You will preventYou will preventYou will preventYou will prevent

nutrient problems by checking and adjustingnutrient problems by checking and adjustingnutrient problems by checking and adjustingnutrient problems by checking and adjusting

your pH in your marijuana grow.your pH in your marijuana grow.your pH in your marijuana grow.your pH in your marijuana grow.

In fact, feeding your plant with the incorrect pH isincorrect pH isincorrect pH isincorrect pH is

one of the most common reasons that plantsone of the most common reasons that plantsone of the most common reasons that plantsone of the most common reasons that plants

develop a develop a develop a develop a cannabis nutrient deficienccannabis nutrient deficienccannabis nutrient deficienccannabis nutrient deficiency. At least

when growers write in to us, incorrect pH is the

cause of a nutrient deficienty at least half of the time.

So if you want to see glistening trichomes on your marijuana, like the

picture to the right, make sure you check and adjust the pH of your water

and marijuana root zone.

How to Test the pH of your Root Zone

You can test the pH of a water sample using a pH Kit or a pH Meter. If

growing your weed in water, take a sample of the water and then test the

pH of your sample .

If your weed is growing in soil or another sort of medium, the easiest way

to get a ball-park figure of the root pH is to test the water going into the

plant as well as the water that runs out of the bottom.

You can assume that the pH of the water that runs out the bottom of your

plant is about halfway between the pH of the water you put in and of the

pH of the root zone.

So for example, if you water your plants with water that has been pH'ed

to 6.0, and the water that comes out the bottom has a pH of 6.5, you can

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Managing pH in my cannabis grow: How to check and adjust the p... http://growweedeasy.com/how-do-i-check-the-pH-of-my-water

1 of 4 8/12/2013 11:58 PM

assume the pH of your root zone must be around 7.0, because the water

that came out was 6.5, which is halfway between 6.0 and 7.0.

When trying to adjust the pH of your root zone, make sure to do all

changes slowly. It is actually worse for your plant to have the pH change

drastically than it is for the plant to have roots in the wrong pH.

Adjust the pH of your Water to Correct Root pH

You will need to add all of your nutrients to your water first before

checking and adjusting the pH. Your nutrients will affect the pH of your

water so it's important they get added before making any adjustments.

It's a good idea to let the pH cover a rangecover a rangecover a rangecover a range instead of always adjusting to

the exact same pH number. Some nutrients are better absorbed at slightly

higher pH readings, while others are absorbed better at lower pH

readings.

If your marijuana plant roots are experiencing the wrong pH, the most

important thing to remember is to make all pH changes to the root zone

slowlyslowlyslowlyslowly (never more than 0.5 points in a day) because rapid changes will

hurt the plant much worse than being at the wrong pH.

For soil soil soil soil an optimum root zone pH optimum root zone pH optimum root zone pH optimum root zone pH is between 6.0 and 7.0, with the most time

spent with a pH between 6.5 - 7.0.

For hydroponics hydroponics hydroponics hydroponics an optimum root zone pH optimum root zone pH optimum root zone pH optimum root zone pH is between 5.5 and 6.5. With

hydroponics, it's especially important to allow the pH to range slightly, as

some nutrients can only be absorbed at higher or lower pH's.

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The thing to remember with pH is that you don'tdon'tdon'tdon't need to be exact. What

you do need is to be consistent in keeping the pH from creeping too high

or too low in your plant root zone.

Here is a video by me, Nebula Haze, which shows you how to easily check

the pH of your water before you use it with your marijuana plants.

Buy a pH Kit from General Hydroponics which also comes with a dropper.

Watch my video on how to manage your pH on Youtube!

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