09/10/2026
Tomato season is the best time to think ahead to next year's garden.
Wet fermentation is the traditional way to save tomato seed. It replicates the process that happens in nature when a ripe tomato falls from the vine and gradually breaks down on the soil. Soaking seeds and pulp in water for a few days dissolves the gel coating that blocks germination, guards against seed-borne disease, and lets viable seeds sink while duds and pulp float away. Rinse, dry, and they're ready to store.
Save your seeds now with these easy steps:
1. Select tomatoes from your healthiest heirloom tomato plants. Squeeze or scoop the seeds and surrounding pulp into a small jar; cover with ~1 inch of water.
2. Cover jar loosely (don't seal) and let sit 3–5 days in a cool spot until a white, frothy film forms on top (sour smell is normal — that's the gel coating breaking down). A layer of fuzzy white or gray mold on top is also normal and actually a sign the process is working.
3. Swirl the liquid in the jar to separate the organic material from the seeds. The viable seeds will sink to the bottom of the jar. Skim off top layer and any floating seeds. Rinse remaining seeds using a fine mesh strainer to remove any pulp.
4. Spread the seeds out on a tray or paper plate to dry. Label the tray with the seed variety and the date. Let dry for 2 to 4 weeks. Once they are completely dry, package seeds in an envelope or jar and store seeds away from light, heat and moisture.
