Grow Your Own, Nevada! Fall 2012: Saving Seeds from Your Garden

Saving Seeds for a Food-Secure FutureHeidi KratschArea Horticulture Specialist

What is a Seed?

OProduct of sexual reproduction

OMaximizes genetic diversity

Genetic diversity is decreasing

O95% of human food needs now provided by just 4 crops: rice, wheat, corn, potatoes.

OIndustrial agriculture focuses on only a handful of cultivars.

O75% of agricultural genetic diversity disappeared in the last century.

Wheat Stem Rust (Ug99)

OFirst identified in Uganda in 1999.

OHas spread through Africa into the Middle East.

O~90% of world’s wheat is defenseless against this virulent strain.

Puccinia graminis

The Irish Potato Famine

Panama DiseaseO1950s – ‘Gros

Michel’ – wiped out!

OToday – ‘Cavendish’- it’s dying!

OFuture – do we need a new cultivar?

The Corn Monoculture

Bringing back biodiversity

Diversity is nature’s survival

wild card.

Plant and Save

Seeds!

Step 1: Avoid growing F1 hybrids

OAlmost all corn seed

OMany varieties of cross-pollinated species

OMust buy new seeds every year

Choose open-pollinatedOCome true to typeOThe easiest are self-

pollinated: beans, peas, tomatoes, peppers

OHeirloom varieties – saved through generations of families and neighbors

OHistory goes back 12,000 years!

Step 2: Protect varietal purity

Flower Structure

Definition of Terms

OAnnual, biennial, perennialOPerfect flowerOImperfect flowersOVernalizationOMonoecious (single house)

plantsODioecious (two houses)

plants

Self-Pollination

Bagging self-pollinators

Bagging flowers on pepper plants

Plants self-pollinate in the bag

Reemay bagsTreated paper bags

Cross-Pollination

Cross-pollination by insects

OCucurbitsOBrassicasOUmbelliferae

Cross-pollination by wind

OCornOSpinachOBeetsOChard

Isolate plants that readily cross-pollinate

ODistanceOTimeOBaggingOCaging

Pollination Cages

OFrame:OWoodOWireOPlastic pipe OMetal tubing

OCovered with:OSpun

polyester cloth (Reemay)

OWindow screen

Alternate Day CagingONeed a

minimum of two cages.

OAlternate days open to pollinators.

Kale and cabbage will readily cross pollinate.

Caging with

pollinators

1

4

2

3

Step 3: Rogue plants for trueness to type

Select desirable characteristics

OVigorOEarlinessODrought

resistanceOInsect resistanceOFlavorOLate bolting in

cool-season crops

Ample population sizeOEspecially

important for cross-pollinating plants.

OSelect a minimum of 6 plants for seed saving.

OMore plants = more genetic diversity

Questions?

Step 4: Harvest Seeds

Overwintering Biennials

OSeed-to-seed method

vs.OSeed-to-root-to-

seed method

OBiennials include:O Carrot, celery,

parsleyO Beet, chardO Leek, onionO Rutabaga, turnip,

parsnipO Broccoli, kale,

brussels sprouts

Root Cellarin

g

Onions (Allium cepa) Cepa group

OBiennial, cross-pollinating (insect)

OOverwinter in ground or lift bulbs.

OBulbs – harvest seed first season

OSeed – harvest seed second season.

Don’t wait too long to harvest seed or the seed heads will shatter!

Broccoli (Brassica oleracea)

OBiennial, cross-pollinating (insect)

OWill cross with all other plants of this species.

ODo not eat plants grown for seed.

OUse cold frame, small hoop house to overwinter.

Beets and Chards (Beta vulgaris)

Biennial, cross-pollinated (wind) – bag or cage

Up to 4 feet tall!

Spinach (Spinacia oleracea)Male plant with flowers

Female plant with seeds

Dioecious, annual, cross-pollinating (wind)

Lettuce (Lactuca sativa)

OSelf-pollinating annual

OBolts in response to lengthening days

OHead-lettuce types need to be slit to allow seed stalk to emerge.

O Seeds ripen 12-24 days after flowering

Squash (Cucurbita pepo)Acorn, yellow crookneck, scallop, zucchini

OMonoecious, cross-pollinating (insect) annual

OCut fruit from vine and let sit for 3 weeks or longer before harvesting seed. Male flower Female flower

Pea (Pisum sativum)OSelf-pollinating

annualOAllow pods to dry

on the vine.OFreeze pods in

airtight container for 3-5 days to kill weevil eggs. Peas and beans are easy

for beginning seed savers.

Carrot (Daucus carota)OBiennial, cross-

pollinated (insect)OUse seed-to-root-

to-seed method OUmbels can be

left to dry on the plant, or

OCut and air-dry.ODe-bearding is

unnecessary.

Corn (Zea mays)OCross-pollinated

(wind) annualOTassels vs. silksOGrow in blocksOSusceptible to

inbreeding depression

ODry ears on the stalk, or remove and dry under shelter

Step 5: Clean seeds

ODry processing

OWet processingOFermentingORinsingODecanting

Dry processing – threshing, winnowing

Wet processing

ORemove seeds from fruit

OWash and rinse

OAir-dryOFerment –

tomato, cucumber

Tomato seeds must be fermented to remove gelatinous coating.

Fermentation

Step 6: Store seeds

OExcellent storage produces vigorous seeds.

OTwo enemies:OHigh

temperatureOHigh moisture

Long-term storage

OCool, dry conditions

OEnvelopesOMoisture-proof

container or freezerOMust be “very

dry.”

Getting to “very dry”

OFan/air conditioner

OFood dehydrator

OSilica gelOCheck daily

until between 5-7% moisture

Testing for Dryness

OWeigh before and after drying slowly in an oven at low temperature.

OSeed moisture content (%) = fresh seed weight – dry seed weight ÷ dry seed weight × 100%

Long-term storage

OFrozen seeds last up to 10 times longer

OStore in paper envelopes with silica gel “dessicant” for one week.

OAllow frozen sealed jar to reach room temp before opening

Supplies:OSeed Savers

Exchange – www.seedsavers.org

Keep good recordsOKeep a card for

each variety.O Plant and varietyO Source, date

obtainedO Germination %O Date storedO Accession numberO Last year grown

Veggies generally not grown from seed

OPotatoOGarlicOArtichokeOAsparagusOSweet potatoORhubarb

Questions?