Saving Seed from the Garden

Every year a few gardeners ask about saving seed from their flowers and vegetables. We would not have the wonderful heirloom varieties if someone hadn’t kept the seeds year to year. Seed saving can be a rewarding and cost saving way to garden, but beware of the pitfalls.

Not every plant’s seeds are worth keeping. Hybrid plants are developed by crossing specific parent plants. Hybrids are wonderful plants but the seed is often sterile or does not reproduce true to the parent plant. Therefore, never save the seed from hybrids. Another major problem is some plants’ flowers are open pollinated by insects, wind or people. These plants include squash, cucumbers, melon, parsley, cabbage, chard, broccoli, mustard greens, celery, spinach, cauliflower, kale, radish, beets, onion, and basil. These plants cross with others within their family. The only way to maintain the original variety is to isolate by large distances. Isolation is often impossible or impractical in a home garden.

Some seeds may transmit certain diseases. A disease that infected a crop at the end of the growing season may do little damage to that crop. However, if the seed is saved and planted the following year, the disease may severely injure or even kill the young plants.

What can you save? Standard or heirloom varieties that are not cross-pollinated by nearby plants are good candidates. Many gardeners successfully keep beans, tomatoes, lettuce, and peppers. Plants you know are heirloom varieties are easy to save. Ask the person or organization you obtained the seed from how they did it. Some people like to experiment, but make sure you don’t bet the whole garden on saved seed.

When saving seed, always harvest from the best. Choose disease-free plants with qualities you desire. Look for the most flavorful vegetables or beautiful flowers. Consider size, harvest time and other characteristics.

Always harvest mature seed. For example, cucumber seeds at the eating stage are not ripe and will not germinate if saved. You must allow the fruit and seed to fully mature. Because seed set reduces the vigor of the plant and discourages further fruit production, wait until near the end of the season to save fruit for seed.

Seeds are mature or ripe when flowers are faded and dry or have puffy tops. Plants with pods, like beans, are ready when the pods are brown and dry. When seeds are ripe they usually turn from white to cream colored or light brown to dark brown. Collect the seed or fruits when most of the seed is ripe. Do not wait for everything to mature because you may lose most of the seed to birds or animals.

Beans, peas, onions, carrots, corn, most flowers and herb seeds are prepared by a dry method. Allow the seed to mature and dry as long as possible on the plant. Complete the drying process by spreading on a screen in a single layer in a well-ventilated dry location. As the seed dries the chaff or pods can be removed or blown gently away. An alternative method for extremely small or lightweight seed is putting the dry seed heads into paper bags that will catch the seed as it falls out.

Seed contained in fleshy fruits should be cleaned using the wet method. Tomatoes, melons, squash, cucumber and roses are prepared this way. Scoop the seed masses out of the fruit or lightly crush fruits. Put the seed mass and a small amount of warm water in a bucket or jar. Let the mix ferment for two to four days. Stir daily. The fermentation process kills viruses and separates the good seed from the bad seed and fruit pulp. After two to four days, the good viable seeds will sink to the bottom of the container while the pulp and bad seed float. Pour off the pulp, water, bad seed and mold. Spread the good seed on a screen or paper towel to dry.

Seeds must be stored dry. Place in glass jar or envelopes. Make sure you label all the containers or packages with the seed type or variety, and date. Put in the freezer for two days to kill pests. Then store in a cool dry location like a refrigerator. Seed that molds was not sufficiently dry before storage.

Seed viability decreases over time. Parsley, onion, and sweet corn must be used the next year. Most seed should be used within three years.

Seed saving is essential for maintaining unusual or heritage vegetables and flowers. It is a great way to propagate many native plants too. There are numerous seed saver exchanges, clubs, and listings in magazines like Organic Gardening. Although you shouldn’t base your entire garden on saved seed you may want to give seed saving a try.

August - September 2000: Gypsy Moth: Know the Facts | Flood Tolerant Trees | Saving Seed from the Garden | Ideal Time for Lawn Renovation