Store and collect Tomato seeds
Seeds from many plants can be saved simply by collecting them as they dry, however, tomatoes require a bit more effort. Tomato seeds are enclosed in a gelatinous sac that contains growth inhibitors and prevents the seeds from sprouting before they’ve buried themselves in the soil. This gel residue can be a problem for stored seeds as it can house seed-and soil-borne diseases, so the best way to remove this gel covering before storage is to allow the seeds to ferment. Follow this easy step-by-step guide and start storing your favourite tomato varieties for next season’s planting.
1. Gather your gear
- Ripe/mature tomatoes - Sharp knife - Glass container - Strainer - Wooden spoon - Paper towel - Envelope - Pencil *Important: Choose your best-looking tomatoes so the next year’s plant will have good genes. Seeds from F1 hybrid varieties, which are bred from two parent varieties, won’t produce the same type of tomato next year, so only save seed from open-pollinated tomatoes, including all the heirloom/heritage varieties.
2. Scoop or squeeze seeds into the container
Cut the tomato open and scoop the fleshy pulp containing the seeds into a glass container. Smaller tomatoes can simply be burst and squeezed out into the jar.
3. Add water and label
If there is not enough liquid from the tomato pulp for the seeds to float in, add a cup of water to help separate the seeds from the pulp. Label the container with the tomato variety and date harvested.
4. Leave to ferment
The gel surrounding the seed inhibits germination and must be removed. To break down this seed coat, leave the seed for two to four days to ferment. This will also kill off many of the harmful bacteria and fungi lurking on the seeds.
5. Swirl the container daily
Gently swirl the container once or twice daily to submerge the pulpy material and prevent the build-up of mould harmful to the seeds.
6. Decant and wash
The seeds are ready for cleaning when the pulp floats to the top and seeds have settled at the bottom. Carefully skim off the pulp, then decant the liquid and seeds into a strainer. Wash the seeds under running water with the back of a wooden spoon to gently remove any remaining material stuck to them so that only the clean seeds remain.
7. Leave the seeds to dry
Spread the seeds on a paper towel to remove excess water. Transfer the seeds to a non-stick surface like a plate or tray and leave them out to dry in a warm place, out of direct sunlight. It usually takes about 2-3 weeks to completely dry out. During the dying process ensure that the seeds dry out evenly and do not clump.
8. Package, label and store
Once the seeds are thoroughly dry, gently scrape the seeds into an envelope. Remember to label it with the tomato variety and date harvested. Store the seeds in a dry place with a cool steady temperature. Properly stored tomato seeds can stay viable for up to six years.