Soil Nutrients

Chapter #8

What nutrients do plants get from the air and water?

• Carbon• Hydrogen• Oxygen

What are the Primary Nutrients?

• Nitrogen• Phosphorous• Potassium

What are the Secondary Nutrients?

• Sulfer• Calcium• Magnesium

What are the Micronutrients?

• Iron• Boron• Zinc• Manganese• Copper• Molybdenum• Chlorine

What are the 16 essential nutrients?

• C HOPKNS CaFe Mg B Mn CuZn ClMo

Functions of Primary Nutrients and the deficiency symptoms?

• Nitrogen: other than water, most important, determines rate of growth– deficiency: yellowing of leaves

• Phosphorous: needed most during germination and during fruit/seed formation– deficiency: stunted growth, purple color

in leaves

• Potassium: mostly regulatory– deficiency: stunted growth, mottled

leaves

Are there non-essential plant nutrients that need to be considered?

• Yes, iodine and cobalt are essential in animals but found in plants

Why is a knowledge of soil nutrients necessary?

• maximize yield• maximize profit• maintain soil fertility

How do you determine soil fertility?

• soil testing• manage organic matter• fertilize

What is Fertilizer Analysis?• it is the amount of the different

nutrients found in a fertilizer• the amount is listed as a percent• it is ALWAYS listed Nitrogen-

Phosphorous-Potassium (N-P-K)• a fertilizer labeled 10-15-10 is 10%

Nitrogen, 15% Phosphorous, and 10% Potassium

• if there is a fourth letter it is for Sulfer

How many pounds of Nitrogen are in a 50# bag of 10-15-10?

• 10% of 50# = 5# Nitrogen

Pounds of Actual Nutrients in a 50# bag of 10-15-10?

• add up 10+15+10 = 35% nutrients or 17.5#

What is the other 65% of this bag?

• inert matterials (filler)

AnalysisA hobby gardener buys a bag of

"Scott's Turfbuilder" uptown for $31.95. The bag weighs 62# and has an analysis of 22-3-3-10.

• How many pounds of actual nutrients?– 17.2#

• What is the cost per pound of actual nutrients?– $1.86

Analysis

A similar analysis of "Farmers Grade Fertilizer" runs about $0.40 per pound of actual nutrient.