Saving Tomato Seeds

Which tomatoes can you save seed from?

Save seed from open-pollinated or heirloom varieties, which grow true to type. Seed from a hybrid usually gives plants unlike the parent, and often poorer ones, so a hybrid is not worth saving. Check the packet or the plant tag if you are not sure.

Do not save from a store-bought tomato unless you know its variety and are willing to experiment, since many are hybrids bred for shipping. Seed saved from plants you grew and tasted is far more useful, because you know how they performed in your garden.

Will your varieties cross with each other?

Most tomato flowers pollinate themselves, so crossing between neighboring varieties is uncommon. Some types, especially varieties with flowers that extend past the petals, are more open to insects and can cross more often. If you want to be certain, separate varieties by some distance, plant tall barrier crops between them or bag a few flower clusters before they open.

Ask your extension office about the distances suited to your area, and record which varieties grew close together. If you grow only a few varieties, the risk is low.

Keep tomato and pepper plants in mind when you plan, since both are in the same plant family but do not cross with one another.

• Plant varieties with some space between them.
• Bag a flower cluster for extra certainty.
• Label the bagged cluster and later the fruit.
• Keep notes on neighbors.

How do you choose the fruit?

Pick from healthy plants with the traits you want: flavor, vigor, disease tolerance and timing. Choose fully ripe fruit, since seed from unripe fruit may not be mature. Avoid fruit from plants with disease, since some tomato diseases can travel with seed.

Mark the parent plants early and save from several of them to keep the variety strong. If a plant produced oddly, it may be a stray cross, and its seed is best skipped.

How do you separate the seed from the pulp?

Each tomato seed is wrapped in a gel coat that slows sprouting. Many guides describe a fermentation method: scoop seed and pulp into a container, label it, leave it at room temperature for a short time while the gel breaks down, and then rinse the clean seed in a fine strainer. Timing and temperature affect the result, so follow a published guide from your extension service and watch the container so that seed does not start to sprout.

This is seed processing and not a food preservation method. Do not eat or use the fermenting material, and keep it out of reach of children and pets.

Use a clean container and label it right away, so the variety is never confused. Rinse seed until the water runs clear, and discard seed that floats and any pulp that remains.

How do you dry tomato seed?

After rinsing, spread seed in a single layer on a non-stick surface, such as a ceramic plate or glass, and let it dry in a warm, airy spot out of direct sun. Paper towels can bond to the seed. Stir the seed from time to time to keep it from clumping, and dry until the seed is completely hard and no longer sticks.

Fully dry seed stores well. Seed that is still damp can mold or lose viability in storage, so be patient and allow extra days if the weather is humid.

How do you label and store the seed?

Put the dry seed in a labeled paper envelope or a sealed container with the variety, the year and any notes. Keep it in a cool, dry, dark place. Seed stored in a damp basement or a hot shed will deteriorate sooner.

Test germination before the next season if the seed is more than a year old. A damp paper towel test shows you how much of it is alive, so you know how thickly to sow.

What can go wrong?

Common problems include seed from hybrids, seed from diseased plants, seed that was not fully fermented or cleaned, and seed stored damp. Some diseases are carried in or on seed, so save only from healthy plants and use clean containers.

Keep records of the variety, the parent plants, the dates and how the next generation grew. Over a few seasons you will learn which varieties give you the best results and which are not worth keeping. Share a small amount of seed with a neighbor as a backup. If your own supply fails, you can get the variety back, and local gardeners often trade notes on which tomatoes perform best nearby.

Last reviewed: November 12, 2026. Written by the Homestead & Small Farm Editorial Team. See our editorial policy.