Writing · Other
How to Save Heirloom Tomato Seeds
By Richard K. Marshall · Originally published
Your best tomato this year can be your seed for next year.
Heirloom tomatoes are loved for their unique flavors, bright colors and long garden history. If you grow them, save seeds from your best plants. It saves money, and it helps keep the variety alive for the next generation.
Why save heirloom seeds
Heirlooms are open-pollinated. Their seeds grow plants true to type, unlike hybrids. Save the seeds, and your favorite plants come back season after season with the same taste and qualities.
Keep a record first
Before you save seeds, write down a few details so you know which seeds came from which plant, and that you saved from your best.
- Variety: the name, like Cherokee Purple or Brandywine.
- Date and place: when and where you harvested, such as your backyard garden.
- Plant notes: size, flavor and anything else that stood out.
A garden journal or a simple spreadsheet works fine.
How to save the seeds
Tomato seeds go through a short fermentation. It removes the natural coating that can keep them from sprouting.
- Pick the best tomatoes. Choose fully ripe, healthy fruit from your best plants. Better tomatoes, better seeds.
- Scoop out the seeds. Slice the tomato open and scoop the seeds into a small container with some of the pulp and juice.
- Ferment. Add a little water and cover loosely with a paper towel or plastic wrap. Leave it in a warm spot for 2 to 4 days and stir daily. A moldy layer on top is normal. It helps break down the seed coating.
- Clean. When the seeds sink to the bottom, fermentation is done. Skim off the mold and floating bits, then rinse the seeds in a sieve under cold water.
- Dry. Spread the seeds in a single layer on a plate or paper towel. Let them dry for about a week in a cool, dry spot out of direct sun. Stir them every day so they dry evenly.
How to store them
Once they're completely dry, store them so they stay viable.
- Label them. Use small envelopes or jars. Write the variety, the date and any plant notes.
- Keep them cool and dry. A pantry, basement or even the refrigerator works. Keep the temperature between 32°F and 41°F. Avoid humidity and big temperature swings, which shorten seed life.
How long they last
Stored properly, heirloom tomato seeds stay viable for 4 to 6 years, though germination drops a little each year.
To test old seeds, sprout a few between damp paper towels before planting season.
Keep going
Saving seeds is easy and rewarding, and it keeps unique, traditional varieties going year after year.
Once you've got tomatoes down, try peppers, beans and squash. Many vegetables are just as easy to save.
— Richard K. Marshall Lexington, Kentucky
Originally published on X: https://x.com/RichMarshall/status/1837593256403566709 · . Refreshed .