How To Save Tomato Seeds

Credit: Carolyn Herriot

Carolyn Herriot

Cut the tomato in half. Squeeze the seeds into a container and add a plastic label for identification. (Notice the protective gelatinous layer around each seed, which prevents it from germinating.)

Leave the seeds to ferment for four days, during which time a white ‘scum’ will form on top. Fermentation dissolves the gelatinous seed layer, preparing the seeds for future germination, and destroys any seed-borne pathogens. (I put a saucer over the container because fruit flies love this process!)

After four, but no more than five days, rinse the seeds in a large bowl by filling the bowl with water. Good viable seeds sink to the bottom, and ‘dud’ seeds float to the top. Gently pour the water and floating ‘scum’ off, repeating the rinsing as many times as you need, until all that’s left in the bottom of the bowl are cleaned seeds. Pour these into a sieve and give them a final rinse; tap off any excess moisture.

Spread the seeds onto a plate to dry. Keep the label on the plate, so you don’t muddle up which varieties are being collected. (I avoid drying seeds on paper towel, as seeds stick to it and have to be picked off, although some people tell me they sow the seeds stuck on the paper towel!) Place the plates of seeds in a sunny window for a day or two to dry them. Crumble the seeds with your fingers to separate any that are stuck together. Store the seeds in labeled, airtight tubs. Tomato seeds stored properly will germinate for at least five years.