Saving seed is one of those skills that sounds complicated until you do it once, and then it becomes obvious. The basic principle is simple: let your best plant produce its best fruit, collect the seed, dry it, and store it somewhere cool and dark. The details vary by crop, but the logic is always the same.
Which crops are easiest to start with ¶
Tomatoes, beans, peas, and courgettes are the easiest crops to save seed from because they are self-pollinating, which means they do not need isolation from other varieties to come true. Start with one of these. Tomatoes are particularly satisfying because the seed-saving process (the wet fermentation method) is slightly dramatic and the results are reliable.
The wet method for tomato seeds ¶
Cut a ripe tomato and squeeze the seeds and gel into a small jar. Add a little water and leave it at room temperature for two to three days. The viable seeds will sink to the bottom; the non-viable ones and the gel will float. Pour off the floating material, rinse the seeds in a fine sieve, and spread them on a piece of baking paper to dry. Label them immediately with the variety name and the year. Do not skip the label.
Drying and storage ¶
Seeds need to be fully dry before storage or they will go mouldy. Spread them in a single layer and leave them somewhere warm and airy for at least a week. Then store them in a paper envelope (not a plastic bag, which traps moisture) inside a sealed tin or jar. Keep the tin somewhere cool and dark. A kitchen cupboard away from the cooker works. A fridge works even better.
What to look for when selecting parent plants ¶
Always save from your healthiest, most productive, most true-to-type plants. Never save from a plant that bolted early, showed disease, or produced fruit that was significantly different from what you expected. You are selecting for the characteristics you want to see in next year's crop. This is the part that Fiona Marsh, who ran our June 2026 seed-saving workshop, emphasised most strongly: selection is everything.
Once you start saving seed, it is hard to stop. You begin to see your garden differently, as a source of next year's plants rather than just this year's food. Our seed library at Green Roots Collective runs on exactly this principle.