Seed Saving Cheatsheet – According to Complexity

Beginner

Bean, Lettuce, Pea, Pepper, Tomato
These vegetables offer the beginning seed saver the best chance for successful seed saving. They produce seed the same season as planted and are mostly self-pollinating, minimizing the need to be mindful of preventing cross-pollination.

Bean - Phaseolus vulgaris

PLANT: Although, ideally, different varieties should be separated by 150 feet or another crop flowering at the same time, cross-pollination is rare even when two varieties are grown next to each other.

FLOWER: Beans produce perfect, self-pollinating flowers. Cross pollination by insects is possible but rare as pollination occurs before the flower opens. Because the anthers are pushed up against the stigma, automatic pollination is assured when the anthers open.

HARVEST: Allow pods to dry brown before harvesting, about six weeks after eating stage.

PROCESS: Small amounts of pods can be opened by hand. Flail larger amounts.

Lettuce - Lactuca sativa

PLANT: Separate varieties flowering at the same time by at least 20 feet to ensure purity.

FLOWER: Lettuce produces perfect, self-pollinating flowers. Each flower produces one seed. Flowers are grouped in little heads of 10-25 flowers all of which open at once for as little as 30 minutes.

HARVEST: Some outside leaves can be harvested for eating without harming seed production. Allow seed heads to dry 2-3 weeks after flowering. Individual heads will ripen at different times making the harvest of large amounts of seed at one time nearly impossible. Wait until half the flowers on each plant has gone to seed. Cut entire top of plant and allow to dry upside down in an open paper bag.

PROCESS: Small amounts of seed can be shaken daily from individual flowering heads. Rub with hands to remove remaining seeds. If necessary, separate seeds from chaff with screens.

Peas - Pisum sativum

PLANT: Ideally, different varieties need to be separated 50 feet or with another crop flowering at the same time..

FLOWER: Peas produce perfect, self-pollinating flowers. Cross-pollination by insects is possible but rare because pollination occurs before the flower opens. Because the stigma does open before pollen is ready crosses theoretically could occur.

HARVEST: Allow pods to dry brown before harvesting, about four weeks after eating stage.

PROCESS: Small amounts of pods can be opened by hand. Flail larger amounts.

Pepper - Capsicum annuum

PLANT: Most home gardeners will get satisfactory results if different varieties are separated by 50 feet and another tall, flowering crop. New studies from New Mexico State University show more crossing than was previously thought. We recommend at least 400 feet between varieties to ensure absolute purity.

FLOWER: Peppers produce perfect, mostly self-pollinating flowers. Solitary bees will pollinate if a more desirable pollen is not available in the area.

HARVEST: Harvest mature, fully-ripe peppers for seed. (Most bell peppers turn red when fully mature.)

PROCESS: There are two methods, dry and wet, to process pepper seeds. The dry method is adequate for small amounts. Cut the bottom off the fruit and carefully reach in to strip the seeds surrounding central cone. In many cases, seeds need no further cleaning. To process the seed from large amounts of peppers, cut off the tops just under the stem, fill a blender with peppers and water and carefully blend until good seeds are separated and sink to bottom. Pepper debris and immature seeds will float to the top where they can be rinsed away. Spread clean seeds on paper towel and dry in cool location until seed is dry enough to break when folded.

Tomato - Lycopersicon esculentum

FLOWER: Tomatoes produce perfect, self-pollinating flowers. Anthers are fused together into a little cone that rarely opens until pollen has been shed and the stigma pollinated. (Older varieties with wild tomatoes or L. pimpinellifolium in their genetic ancestry may have stigmas that stick out beyond the cone containing the anthers. Varieties with this trait can be identified by looking closely at mature flowers and need to be treated accordingly.)

HARVEST: If possible, allow tomatoes to completely ripen before harvesting for seed production. Seeds from green, unripe fruits will be most viable if extracted after allowing the fruits to turn color.

PROCESS: Cut the tomato into halves at its equator, opening the vertical cavities that contain the seeds. Gently squeeze out from the cavities the jelly-like substance that contains the seeds. If done carefully, the tomato itself can still be eaten or saved for canning, sun-drying or dehydrating.

Place the jelly and seeds into a small jar or glass. (Add a little water if you are processing only one or two small tomatoes.) Loosely cover the container and place in a warm location, 60-75° F. for about three days. Stir once a day.

A layer of fungus will begin to appear on the top of the mixture after a couple of days. This fungus not only eats the gelatinous coat that surrounds each seed and prevents germination, it also produces antibiotics that help to control seed-borne diseases like bacterial spot, canker and speck.

After three days fill the seed container with warm water. Let the contents settle and begin pouring out the water along with pieces of tomato pulp and immature seeds floating on top. Note: Viable seeds are heavier and settle to the bottom of the jar. Repeat this process until water being poured out is almost clear and clean seeds line the bottom of the container. Pour these clean seeds into a strainer that has holes smaller than the seeds. Let the excess water drip out and invert the strainer onto paper towel or piece of newspaper. Allow the seeds to dry completely (usually a day or two). Break up the clumps into individual seeds, label and store in a packet or plastic bag.

Experienced

Corn, Cucumber, Muskmelon, Radish, Spinach, Squash/Pumpkin. 
The experienced seed saver's vegetables produce seed the season they are planted but require separation to keep unwanted cross-pollination from taking place

Corn - Zea mays

PLANT: Female corn flowers are pollinated predominately by the wind, rarely by insects. Pollen is light and can be carried great distances. For purity, separate two varieties pollinating at the same time by at least 1 mile. Reasonable results are obtained with separation of 1000 feet.

FLOWER: Corn is monecious, producing separate male and female flowers on each plant. Male flowers appear as tassels on the top of corn stalks and female flowers are pollinated via the silk emerging from each ear.

INBREEDING DEPRESSION: Corn is susceptible to intense inbreeding depression. If seed is saved from too few plants, subsequent plants may be short, mature late and produce few ears. Grow at least 200 plants and save the seeds from at least 100 of the best.

HARVEST: Corn seed is usually ready to be harvested 4-6 weeks after eating stage.

PROCESS: Process all but very large amounts of seed by gripping dried ears by hand and twisting allowing kernels to fall into container. Any remaining silk and chaff can be winnowed.

Cucumber - Cucumis sativus

(All cucumbers except Armenian cucumbers which are Cucumis melo)

PLANT: Separate two different cucumber varieties by at least 1/2 mile, or segregate by time to ensure purity. Experienced, home, seed savers can grow more than one variety at a time in a single garden by using hand pollinating techniques.

FLOWER: Cucumbers are mostly monoecious with separate male and female flowers on each plant. Female flowers can be identified by locating the ovary (a small looking cucumber) at the base of the flower. Cucumber vines will produce the greatest amount of female flowers when day length shortens to approximately 11 hours per day. Fruits will be aborted during dry spells and very hot weather.

INBREEDING DEPRESSION: Although inbreeding depression is not usually noticeable in cucumbers, seeds should be saved from at least 6 cucumbers on 6 different plants.

HARVEST: Cucumbers raised for seed cannot be eaten. They should be left to ripen at least 5 weeks after eating stage until they have turned a golden color.

PROCESS: Slice fruit lengthwise and scrape seeds out with spoon. Allow seeds and jelly-like liquid to sit in jar at room temperature for 3 or 4 days. Fungus will start to form on top. Stir daily. Jelly will dissolve and good seeds will sink to bottom while remaining debris and immature seeds can be rinsed away. Spread seeds on a paper towel or screen until dry. (See instructions for tomato.)

Muskmelon - Cucumis melo

Divided below into seven separate groups because of similar features. All C. melos varieties in all groups will cross with each other. They will not cross with watermelons which are Citrullus vulgaris. 
Indorus: honeydew, crenshaw, casaba
Conomon: Asian, pickling melons
Dundaim: pocket melon
Cantalupensis: true cantelopes (without netted skin)
Flexuosus: Armenian cucumbers
Reticulatus: Persian melons, muskmelons with netted skin and orange flesh
Chito: orange melon, garden lemon melon

PLANT: Separate two different muskmelons by at least 1/2 mile or separate by time to ensure purity. Experienced, home, seed savers grow more than one variety at a time in a single garden by using hand pollinating techniques. Muskmelon flowers are small and relatively difficult to hand pollinate.

FLOWER: Muskmelons are mostly monoecious with separate male and female flowers on each plant. Female flowers can be identified by locating the ovary (a small looking melon) at the base of the flower. The early flowers are the most likely to be successfully pollinated and eventually produce seeds.

INBREEDING DEPRESSION: Not usually a problem with muskmelons.

HARVEST: Muskmelon seed is mature and can be harvested from ripe and ready to eat muskmelons.

PROCESS: Simply rinse seeds clean, dry with towel and spread on board or cookie sheet to complete drying.

Radish - Raphanus sativus

PLANT: Separate different varieties being grown for seed at the same time by at least 1/2 mile to ensure purity. Satisfactory results for home gardeners require no more that 250 feet of separation. As radishes cannot self-pollinate, pollen must be carried by insects from plant to plant.

FLOWER: Radishes produce annual flowers which require pollination by insects, primarily bees.

HARVEST: Harvest 3' tall stalks containing seeds pods when pods have dried brown. Pull entire plant and hang in cool, dry place if all pods are not dried at the end of the growing season.

PROCESS: Open pods by hand for small amounts of seed. Pods that do not open when rubbed between hands can be pounded with hammer or mallet. Winnow to remove remaining chaff.

Spinach - Spinacia oleracae

PLANT: It is probably best to grow seeds for only one variety of spinach at a time. Remove plants which bolt first, and thin remaining plants to 8" for seed production. Leave one male plant for each two females to ensure pollination.

FLOWER: Spinach is "dioecious", with male and female flowers on separate plants. Flowers are wind pollinated by spinach's dust-like, powdery pollen which can be carried for miles..

HARVEST: Some outside leaves can be harvested for eating without harming seed production. If possible, wait until all plants have dried brown. Pull entire plant and hang in cool, dry place if necessary at the end of the growing season.

PROCESS: Strip seeds in upward motion and let them fall into container. Chaff can be winnowed. Use gloves for prickly-seeded types.

Squash/Pumpkin -

Cucurbita maxima varieties with large, hairy leaves, long vines and soft, hairy stems and include: banana squashes, buttercups, hubbards and marrows

Cucurbita mixta varieties with large, hairy leaves, long vines and hard, hairy stems and include the cushaws

Cucurbita moschata varieties similar to C. mixta with flaring stems at the fruit and large, green sepals surrounding the flowers and include: butternuts

Cucurbita pepo varieties with prickly stems and leaves with a hard, five-angled stem and include: acorn squashes, cocozelles, pumpkins, crooknecks, scallops, spaghetti squashes and zucchinis

PLANT: Squashes from different species (see above) can be grown next to each other. Separate different squash varieties in the same species by at least 1/2 mile to ensure purity. (Some crossing between C. mixta and C. moschata has been reported recently.) Experienced, home, seed savers grow more than one variety in a single garden by using hand pollinating techniques. Squash flowers are large and relatively easy to hand pollinate.

FLOWER: Squashes are monoecious with male flowers and female flowers on each plant. Female flowers can be identified by locating the ovary (a small looking squash) at the base of the flower. (Some female flowers have stamens.)

INBREEDING DEPRESSION: Not usually noticed in squash and pumpkins.

HARVEST: Squash must be fully mature before harvested for seed production. This means that summer squashes must be left on the vine until outer shell hardens. Allow to cure 3-4 additional weeks after harvest to encourage further seed ripening.

PROCESS: Chop open hard-shelled fruits and scoop out seeds. Rinse clean in wire strainer with warm, running water. Dry with towel and spread on board or cookie sheet to complete drying

Expert

Beet/Swiss Chard, Cabbage Family, Carrot,  Escarole/Frissee,  Onion,Radicchio/Endive,  Turnip/Chinese Cabbage. 

Beet/Swiss Chard - Beta vulgaris

PLANT: Grow seed for only one variety of beet or Swiss chard at any one time.

FLOWER: Beets and Swiss chard produce perfect flowers. Pollen is light and can be carried for miles by the wind.

INBREEDING DEPRESSION: Save seed from at least 6 different beets to ensure genetic diversity and vigor.

HARVEST: Cut 4' tall tops just above the root when majority flowering clusters have turned brown. Tops can be stored in cool, dry locations for 2-3 weeks to encourage further seed ripening.

PROCESS: Small quantities of seed can be stripped by hand as seed matures. Large numbers of tops can be put into a cloth bag and stomped or pounded. Chaff can be winnowed.

Cabbage Family - Brassica oleracea
Please Note: All check outs of Brassica oleracea do NOT require returned seed. Best Practices has concluded the difficulty level of returning pure seeds (seed not crossed with other varieties) is too high. SLOLA will continue to buy these seeds, as well as others as needed to keep our seed genetics reliably certain. 

Includes broccoli, brussels sprout, cauliflower, cabbage and kale.

PLANT: All vegetables and varieties in this large species will cross with each other. Separate different varieties at least 1000 feet for satisfactory results or at least 1 mile for purity. Caging with introduced pollinators or alternate day caging is also recommended in small gardens.

FLOWER: Flowers are perfect, most of which cannot be self-pollinated. Necessary cross-pollination is performed by bees. The stigma becomes receptive before the flower opens, and pollen is shed hours after the flower opens.

INBREEDING DEPRESSION: Plant at least 6 different plants to protect vigor and ensure a reasonable amount of genetic diversity.

HARVEST: Broccoli, cauliflower, cabbage and kohlrabi heads grown for seed should not be trimmed for consumption. Brussels sprouts, collards and kale can be lightly trimmed for eating without affecting quality seed production. If small amounts of seeds are wanted, allow individual pods to dry to a light brown color before picking and opening by hand. Lower pods dry first followed by those progressively higher on the plant. For larger amounts of seeds pull entire plant after a majority of pods have dried. Green pods rarely produce viable seeds even if allowed to dry after the plant is pulled.

PROCESS: Smash unopened pods in cloth bag with mallet or by walking on them. Chaff can be winnowed.

Carrot - Daucus carota

PLANT: Separate different varieties at least 1/2 mile to ensure purity. (Queen Anne's Lace or wild carrot will cross with garden carrot.) Alternate day caging or caging with introduced pollinators allows two or more varieties to be grown for seed in small gardens.

FLOWER: Carrots produce perfect flowers that are cross-pollinated by a number of insects. Flowers are arranged in round, flat groups called umbels.

INBREEDING DEPRESSION: Carrots can exhibit severe inbreeding depression. Save and mix seed from as many different carrots as possible.

HARVEST: For small amounts, hand pick each umbel as it dries brown. Large amounts of seed can be harvested by cutting entire flowering top as umbels begin to dry. Allow to mature in cool, dry location for an additional 2-3 weeks.

PROCESS: Clean small amounts by rubbing between hands. Larger amounts can be beaten from stalks and umbels. Screen and winnow to clean. Carrot seed is naturally hairy or "bearded". Debearding in the cleaning process does not affect germination.

Onion - Allium sp.

Varieties within each onion species will cross with each other. Crosses between species although not common, are possible.
Allium schoenoprasum: Common chives
Allium tuberosum: Garlic chives
Allium fistulosum: Japanese bunching onions (Occasional crossing between A. fistulosum and A. cepa has been observed.)
Allium cepa comprised of three groups: Aggregatum includes shallots, multiplier onions and potato onions; Cepa our biennial, common storage and slicing onions; Proliferum includes the Egyptian or walking onions.

PLANT: Separate from other flowering Alliums of the same species at least 1000 feet for satisfactory results or at least 1 mile for purity. Caging with introduced pollinators or alternate day caging is also recommended in small gardens. 

FLOWER: The Alliums produce perfect flowers, most of which are cross-pollinated because stigmas in each flower become receptive only after pollen in that flower is shed. Flowers in an individual umbel open and shed pollen at different times so crosses can and do occur on the same plant. Cross-pollination is performed mostly by bees.

INBREEDING DEPRESSION: Onions display a fair amount of inbreeding depression after two or three generations of self-pollination. Save and mix the seeds from at least two different plants.

HARVEST: Clip umbels as soon as majority of flowers have dried. Seeds will start dropping from some flowers at this time so check often. Allow to dry in cool, dry location for up to 2-3 weeks.

PROCESS: Fully dried flowers will drop clean seeds naturally. For small amounts, rub remaining flowers to free seeds. For larger amounts, rub heads over screens. Winnow to remove remaining debris.