Seed saving from vegetables
Some vegetables are easier to save seed from than others. Any plant that self-pollinates will produce seed that is ‘true’ and these include French beans, peas and many tomatoes. The seed saved from these will usually produce exactly the same plant and cultivar as the parent plant.
Saving seed from F1 hybrids
More difficult, is saving seed from a plant that cross-pollinates. These will ‘cross’ with other cultivars so you may not get exactly the same plant as the parent. Cross-pollinators include broad beans, runner beans, squashes and carrots. Cross-pollination can be overcome by growing only one particular cultivar at a time, or growing different cultivars a certain distance apart (the ‘isolation distance’). A word of caution, F1 cultivars will not breed true even if you grow just one plant and isolate it, so avoid these cultivars when saving seed.
How to save your own seed
Then comes harvesting of the seed, and this will vary from crop to crop. Peas and beans are very easy; wait for the pods to go brown and brittle on the plant, then remove the pods and shell them. It is important that seed to be stored is dry, so I usually lay the peas and beans for another two weeks on trays in a warm, airy space.
When you can press the seed coat with your thumbnail and it makes no impression, the seed is dry enough to store. Place the seed in paper bags, in a cool dry place and they should keep up to three years.
Saving seed from tomatoes
Tomatoes are exciting – soak in water for a few days to ferment the pulp off the seed then dry thoroughly.
With biennials (for example carrots) you’ll need to overwinter the tuber as they flower in their second year.
‘Back Garden Seed Saving’ by Sue Stickland (2008 Eco-logic books) gives crop-by-crop instructions. Your life will soon be full of paper envelopes of seed, I promise.
More on how to save your own seed