Seed Saving to Preserve Today's Bounty for Tomorrow's Gardens

John W. Jett
WVU Extension Service
Extension Specialist - Horticulture

Seed saving has long been the main way to pass plants down from generation to generation. Seed saving is not only fun, it's also an important way to perpetuate heirloom plants and to ensure the genetic diversity of the world's food crops, which are eroding at an unprecedented and accelerating rate. Seed saving has been used successfully for many crops over the years-- the varieties we call "heirloom" are here today because of dedicated gardeners like you and me have faithfully saved seed over the generations.

Saving seed requires you to grow plants to maturity and consequently they get bigger and stay around longer than normal, so leave a bit more space around them. Saving and growing seed, year on year, is taking part in evolution. Saving garden seeds at the end of each growing season can be a great cost saving measure and a way to duplicate last year's delectable harvest.

Seed saving is not always feasible with all types of vegetables, but collecting your own seed can be an exercise in self-sufficiency and a lesson in plant biology. Seeds you save from your home production system are accustomed to your climate and growing medium and are adapted to pests in your area. Seeds are generally saved from annual and biennial plants. Perennials are usually propagated through division or cuttings.

The easiest seeds to save are open-pollinating, non-hybrid annuals. Plants that are not self-pollinating can cross-pollinate; therefore, it is best to grow only one variety of a plant from which you want to save seed that season. If two varieties of spinach bloom near each other, the resultant seed is likely to be a cross between the two. Different varieties of peppers should be separated by 500 feet to avoid cross-pollination. Melons, pumpkins, cucumbers, and squash need even more personal space--at least a half-mile is required.

Biennials require more work and commitment. These plants do not send up seed stalks until the second season. Biennials include beets, Brussels sprouts, cabbage, carrots, cauliflower, celery, onions, parsley, parsnips, rutabaga, salsify, Swiss chard, and turnips.

Do not save seed from hybrid varieties if you want plants like the parents. Seeds from hybrid varieties produce a mix of offspring, many of which may have different characteristics than the parent. Seed from hybrid vine crops is often quite variable also - squashes, cucumbers, melons and pumpkins often cross-pollinate with other genetically compatible varieties. Unless pollination has been strictly controlled, strange hybrids often result in the next generation.

Among the vegetable seeds most easily saved are non-hybrid tomato, pepper, bean, eggplant, cucumbers, summer squash, and watermelons. Collect seeds from the fully mature, ripe fruit of these plants.

Tomato: The seeds are encased in a gelatinous coating, which prevents them from sprouting inside the tomato. Remove this coating by fermenting it. This mimics the natural rotting of the fruit and has the added bonus of killing seed borne tomato disease. Squeeze the seeds from a fully ripe fruit into a bowl, add water and let stand at room temperature for about three days. Once fermentation occurs, mold will form on the surface of the water. Add more water, stir, then gently scrape mold and debris off the top. Repeat until only clean seed remains, strain, rinse, and leave the seeds at room temperature until they are thoroughly dry.

Peppers: Select a mature pepper, preferably one that is completely red. Cut the pepper open, scrape the seeds onto a plate and let the seeds dry in a non-humid, shaded place, testing them occasionally until they break rather than bend. Leave at room temperature until completely dry.

Beans, peas, and other legumes: Leave pods on the plant until they are "rattle dry." Pick the pods and remove the seeds when completely dry.

Eggplant: Leave the plant on the vine until it is well past the stage when you would pick it for kitchen purposes. Eggplants ready for seed saving will be dull, off-colored and hard. Cut the eggplant in half and pull the flesh away from the seeded area.

Cucumbers: Cucumbers change color after they ripen and start to become mushy. Cut it in half and scrape the seeds into a bowl. Remove their slimy coating by rubbing them gently around the inside of a sieve while washing them or soak them in water for two days. Rinse and dry.

Summer squash: Summer squash is at the seed-saving stage when you cannot dent the squash with a fingernail. Cut it open, and scrape the seeds into a bowl, wash, drain, and dry.

Watermelon: Put the seeds from ripe fruit in a strainer and add a drop of dishwashing liquid to remove any sugar from the seeds.

Before you store your seeds, make sure that you have thoroughly dried them. Home-saved seeds will retain their vigor if thoroughly dried and saved in air proof containers in the freezer for extended storage or in a cool dry cellar for next season. While some vegetable seed can remain viable in storage for as long as 15 years or more, and grains may remain viable much longer under stable environmental conditions, every year in storage will decrease the amount of seed that will germinate. When you have processed the seeds and are ready to package for the winter, it pays to buy desicant paks for your storage containers to keep your seeds dry. Seeds should contain 3-5 percent moisture while in storage. General rule is if your can bend your seed then it still has too much moisture in it and will rupture and die if frozen. However, if you attempt to bend it and it breaks instead, then it’s probably at 8% or less and can be safely frozen. Another point is that when you remove the seeds from the freezer, allow them to come up to room temperature before handling for planting or sowing. Saving seeds in storage will safeguard your family's food crop in the event of world-wide catastrophes, war, pandemic outbreaks and other unforeseen disasters.

Storing seeds; Store most seed packets in airtight jars. The exception is legumes, which store best in breathable bags. To keep the seeds dry, fill a small cloth bag with about one-half cup dried powdered milk. Place the packet in the jar beneath the seed packets. Be sure to label your container with the variety, the date, and other pertinent information. Store your seeds in a cool, dark, dry place; a refrigerator is a good choice. Avoid opening the container until you are ready to plant.

Stored seeds will retain their viability for different lengths of time depending on the type of seed. Melon seed can be stored for as long as five years, while sweet corn is only good for one year. Other types of seed remain viable for two to three years.

Plants are pollinated in three differing ways, by wind, insects or by what is known as self-pollination. Plants from the same species can cross with each other producing mixes of the parent plant. Plants with pods, like beans, are ready when the pods are brown and dry. Plants pollinated by wind (such as corn and spinach) and those pollinated by insects (such as squash and cucumbers) may produce a next generation that resembles a parent, or they may cross with other varieties to turn up something entirely unique. In recent decades, there has been a major shift to purchasing seed annually from commercial seed suppliers, and to hybridized or cloned plants that do not produce seed that remains "true to type"-retaining the parent's characteristics- from seed. To be successful at seed saving, new skills need to be developed that enhance the capacity of growers to ensure that desired characteristics are retained in their plant: learning the minimum number of plants to be grown which will preserve inherent genetic diversity, recognizing the preferred characteristics of the cultivar being grown so that plants that are not breeding true are not selected for seed production. Recommended minimums number of plants for seed preservation: 25 cucumbers, squash, melons; 50-100 radishes, brassicas, mustards; 200 sweet corn. Seed saved from these plants will breed true, provided the plants have been properly isolated from different varieties of the same species.

Open-pollinated varieties will grow true to type when randomly mated within their own variety. If two varieties of spinach bloom near each other, the resultant seed is likely to be a cross between the two. Different varieties of peppers should be separated by 500 feet to avoid cross-pollination. The closer the varieties are located, the higher the amount of crossed seeds. Theoretically you should aim for at least half a mile between varieties.

Heirloom vegetables are varieties that are grown, selected, saved, named, and shared by farmers and gardeners. Heirloom plants are accessible now because people have saved seeds for domestic use throughout generations of sustenance farming. You can really cut down on your gardening costs by gardening with heirloom seeds that you save year to year. You can also save heirloom flower seeds such as: cleome, foxgloves, hollyhock, nasturtium, sweet pea, and zinnia. You are in control of heirloom varieties that do best in your garden. Saving your own seeds increases your self-sufficiency; and it can save you money. It is generally accepted that, to be an heirloom, a variety must be open pollinated and be at least fifty years old. And since heirloom seeds and the practice of seed saving also hold hope for helping feed a hungry planet, they're even more compelling today. You can save favorite heirloom seeds for your own use in your garden, breed and improve varieties, swap with friends, join seed-saving organizations, or grow seed commercially at many levels of scale--the possibilities are numerous.

Common methods of preparing your seeds:

1) Allowing the seeds to dry naturally on the plant. Corn and garlic would be a good representative of these method. Pull the corn husks when the corn as fully ripened and allow to continued drying on racks (if protected from birds and squirrels) or in paper grocery sacks indoors until they are thoroughly dried. Then you can twist them in your hands to get the kernels to fall off. Package, label with name of variety and date or year of harvest and store. For garlic, the same drying method applies. Garlic can also be braided and hung from nails, or stored in open woven bags while they are drying. This is also referred to as "curing" when in reference to garlic. Lettuce and cole crops such as broccoli seeds can be collected directly from the plant. When you notice the seeds look dry and about ready to fall off, then you can directly pull the seeds off by hand into a waiting paper bag. How easy can that be!

2) Removing the seeds and allowing to air dry. This would be the most common methods of vegetable seed storage. For example, cucumbers and other squash type plants. Allow the fruits to fully ripen even to the point of the fruit starting to turn yellow so that the seeds inside fully develop. Then cut open the vegetable and scoop out the seeds. I would recommend a gentle washing in a mild bleach solution (one part bleach to ten parts water) and then lay out in a single layer on newspaper or paper towels until the seeds have thoroughly dried. Then store in containers of choice with appropriate labeling.

3) For bean and pea plants, again, allow the pods to ripen fully on the plant, then remove the pods, open and out pop the seeds! You will probably want to let the seeds dry out some more if they appear to be somewhat damp or soft..

4) Fermenting is needed for tomatoes as the viscous gel substance or pulp, inhibits germination so must be removed. The easiest way to do this is to slice open your tomato, squeeze the contents into a glass jar, add water up to about ¾ of the jar, stir and set aside for a few days. You will notice a icky smelly moldy residue collecting on the top of the water as well as some seeds (these are dead seeds). The water will clear and the “good” seeds will sink to the bottom of the jar. After about 4-5 days this process will seem to have come to an end, so carefully scoop out the stuff from the top and throw away, pour off the water down the sink, and then lastly, pour out the seeds from the bottom of the jar onto newspaper or paper towel for the final drying. When the seeds have dried, they can be removed from the paper and stored.