Saving vegetable seeds
You can save vegetable seeds from your garden produce to plant next year. Seed saving involves selecting suitable plants from which to save seed, harvesting seeds at the right time and storing them properly over the winter.
Tomatoes, peppers, beans and peas are good choices for seed saving. These plants have flowers that are self-pollinating, and seeds that require little or no special treatment before storage. Seeds from biennial crops such as carrots or beets are harder to save, since the plants need two growing seasons to set seed.
Plants with separate male and female flowers, like corn and vine crops, may cross-pollinate. It is difficult to keep the seed strain pure. Popcorn can pollinate a stand of sweet corn from a nearby garden on a windy day. This will affect the flavor of the current sweet corn crop, and a crop grown from these seeds will be neither good sweet corn nor good popcorn.
Insects can cross-pollinate cucumbers, melons, squash, pumpkins and gourds. Although cross-pollination will not affect the quality of the current crop, seeds from such a cross will grow into vines with fruit unlike that of the parent plant. This often results in inferior flavor and other characteristics.
When saving seed, choose open-pollinated varieties rather than hybrids. If open-pollinated varieties self-pollinate or cross-pollinate with other plants of the same variety, they set seed that grow into plants that are still very similar to the parent plant. These plants bear similar fruit and set seeds that will produce more plants that are similar.
Open-pollinated varieties may be "heirlooms." Gardeners pass these varieties down through the generations, or they may be selections that are more recent.
Some tomato varieties are not hybrids. They are open-pollinated types such as 'Big Rainbow', 'San Marzano' and 'Brandywine'. Seed produced by these varieties will grow into plants very similar to the parent plants, with nearly identical fruit. Likewise, 'Habanero', 'California Wonder' and 'Corno di Toro' peppers; 'Lincoln', 'Little Marvel' and 'Perfection' peas; and 'Kentucky Wonder', 'Blue Lake' and 'Tendercrop' beans are all open-pollinated varieties that will come true from seed.
Once you have planted an open-pollinated crop, select the plants from which you want to save seed. Choose only the most vigorous plants with the best-tasting fruit as parents for the next year's crop. Do not save seed from weak or off-type plants.
Hybrid vegetable plants are products of crosses between two different varieties, combining traits of the parent plants. Sometimes a combination is particularly good, producing plants with outstanding vigor, disease resistance and productivity. Hybrid seeds are generally more expensive as they cost more to produce.
Hybrid plants, such as 'Big Boy', 'Beefmaster' and 'Early Girl' tomatoes will produce viable seed. Plants grown from that seed are not identical to the hybrid parents. They will be a completely new combination of the good and bad traits of the plants from the initial cross. It is impossible to predict just how the seedling plant will perform or what qualities the fruit will have.
- Allow fruits to ripen fully and scoop out the seeds, along with the gel surrounding them, before you eat or cook the tomatoes.
- Put the seeds and gel in a glass jar with some water.
- Stir or swirl the mixture twice a day. The mixture will ferment and the seeds should sink to the bottom within five days.
- Pour off the liquid, rinse the seeds and spread them out to dry on paper towels.
- Allow some fruits to stay on the plants until they become fully ripe and start to wrinkle.
- Remove the seeds from the peppers and spread them out to dry.
- Save pea and bean seeds by allowing the pods to ripen on the plants until they are dry and starting to turn brown, with the seeds rattling inside. This may be as long as a month after you would normally harvest the peas or beans to eat.
- Strip the pods from the plants and spread them out to dry indoors.
- They should dry at least two weeks before shelling, or you can leave the seeds in the pods until planting time.
Treating seed to prevent disease transmission
Bacterial canker of tomato is in Minnesota gardens. This disease can devastate tomato and pepper plants, and can persist in garden soil. It is very important not to introduce bacterial canker into the garden.
The bacteria can be inside seeds, on the seed coat or in healthy-looking seedlings. If you save seeds from your garden or swap with friends, treat the seed to kill this pathogen
Store seeds in tightly sealed glass containers. You can store different kinds of seeds, each in individual paper packets, together in a large container. Keep seeds dry and cool. A temperature between 32° and 41°F is ideal, so your refrigerator can be a good place to store seeds.
A small amount of silica-gel desiccant added to each container will absorb moisture from the air and help keep the seeds dry. Craft supply stores sell silica gel in bulk for drying flowers.
You can also use powdered milk as a desiccant. Use one to two tablespoons of milk powder from a freshly opened package. Wrap the powder in a piece of cheesecloth or a facial tissue and place it in the container with the seeds. Powdered milk will absorb excess moisture from the air for about six months.
Be sure to label your saved seeds with their name, variety and the date you collected them. It is easy to forget the details by the following spring. Use saved seed within one year. The older the seed the lower the germination and vigor.
Reviewed in 2018