Saving Seeds at Summer’s End: Tomatoes, Beans and Flowers for Next Year

By late August, New England gardens are full of the year’s best performers: the tomato plant that never quit, the beans that climbed the fence, the marigolds that glowed all summer. Saving seeds from those plants is a satisfying, practical way to carry the season forward. It saves money, preserves varieties suited to local conditions and gives gardeners something wonderful to share with neighbors when spring arrives.

Seed saving can sound technical, but many common garden plants are easy for beginners. Here is how to get started.

Understand Which Seeds Grow True

Before you start, it helps to know a few basic terms.

• Open-pollinated varieties, including many heirlooms, produce seeds that generally grow into plants similar to the parent, as long as they have not cross-pollinated with other varieties.
• Hybrid varieties, often labeled F1 on seed packets, are crosses between two parent plants. Their seeds may grow into plants that look and taste quite different from the original.
• Self-pollinating plants, such as tomatoes, beans, peas and lettuce, are less likely to cross with neighboring varieties, which makes them excellent choices for beginners.
• Cross-pollinating plants, such as squash, cucumbers, melons and corn, can easily mix with other varieties nearby, so their seeds may produce surprises.

Start with easy, self-pollinating crops and open-pollinated flowers. You will have great success and learn the basics quickly.

Choose Your Best Plants

Seed saving is a chance to select for the traits you want. Pick seeds from plants that:

• Stayed healthy and free of disease
• Produced well and tasted great
• Handled heat, drought or local conditions better than others
• Matured at a time that suits your garden

Avoid saving seeds from plants that looked sickly, bolted early or produced poor fruit. Over several years of choosing the best plants, gardeners can gradually develop strains that are especially well suited to their own yard or community garden plot.

Saving Tomato Seeds

Tomatoes are a classic first project. The traditional method uses fermentation to remove the gel coating around each seed.

1. Pick a fully ripe tomato from a healthy open-pollinated plant.
2. Cut it in half and squeeze or scoop the seeds and gel into a small jar.
3. Add a little water, cover loosely and label with the variety name.
4. Let it sit at room temperature for two to four days, stirring daily. A layer of mold may form on top; that is normal.
5. Rinse the seeds in a fine strainer once they sink and the gel has broken down.
6. Spread seeds on a plate or coffee filter to dry for one to two weeks, stirring occasionally so they do not clump.

Saving Bean and Pea Seeds

Beans and peas are among the easiest seeds to save.

1. Leave some pods on the plant until they turn dry, brown and papery, and the seeds rattle inside.
2. Pick the pods before heavy rain or frost.
3. Finish drying pods indoors in a single layer if needed.
4. Shell the seeds and spread them out to dry for another week or two.
5. Check that seeds are hard and do not dent when pressed with a fingernail.

Saving Flower Seeds

Many annual flowers are easy to save and wonderful to share.

• Marigolds: let flower heads dry on the plant, then pull out the long, slender seeds.
• Zinnias: let blooms fade and dry, then pull apart the petals to find arrow-shaped seeds at the base.
• Cosmos: collect the thin, dark seeds once seed heads dry.
• Sunflowers: cover heads with a paper bag or mesh to protect seeds from birds, then cut and dry the heads before rubbing seeds loose.
• Nasturtiums: collect the large, wrinkled seeds once they fall or loosen from the plant.

Pollinator-friendly flowers grown from saved seed are a gift to bees and butterflies as well as neighbors.

Drying and Storing Seeds

Proper drying and storage keep seeds viable for future seasons.

• Dry thoroughly. Seeds must be completely dry before storage to prevent mold.
• Store in paper envelopes or small glass jars with tight lids, once seeds are fully dry.
• Keep them cool, dark and dry. A closet or a sealed container in the refrigerator works well.
• Add a silica gel packet to jars to absorb moisture, if available.
• Label everything with plant type, variety, date collected and any notes, such as “best producer” or “early bloomer.”

Most vegetable and flower seeds stay viable for several years when stored well, though germination rates gradually decline over time.

Share the Harvest of Seeds

Saved seeds are made for sharing.

• Package small amounts in labeled envelopes for neighbors and community gardeners.
• Include growing tips on the envelope, such as when to plant and how much sun the plant needs.
• Hold onto a few for a seed swap in late winter, when gardeners are dreaming of spring.
• Ask your local library or community garden whether they have a seed library that accepts donations.

Seed Saving Checklist

• Open-pollinated, healthy plants chosen
• Seeds collected when fully mature
• Tomato seeds fermented, rinsed and dried
• Bean and flower seeds dried on the plant and indoors
• Seeds stored in labeled envelopes or jars in a cool, dry place
• Extras packaged for sharing with neighbors

Every saved seed holds a little piece of this summer’s garden. Plant it next spring, share it with a neighbor, and the story of a good growing season continues for years to come.