Saving seed from your own garden

For a seed to form, a flower must be pollinated: pollen reaches the female part of the flower. Some plants mostly pollinate themselves – they are called self-pollinating. These include beans, peas, tomatoes and lettuce. Because the pollen usually comes from the same flower, unwanted crosses are rare, and the seeds produce plants very similar to the parent.

Cross-pollinating plants such as squash or maize, on the other hand, need pollen from other plants, often carried by insects or wind. If other varieties of the same species grow nearby, they cross easily. Getting true-to-type seed from them requires knowledge of distances and screening – that is why they are not suited for beginners.

F1 hybrids are created when breeders deliberately cross two different parent lines. The first generation is very uniform. Their offspring, however, segregate into different forms – some resemble one parent, some the other, some neither. That is why it is not worth saving seed from F1 plants.

Choose the best plants as seed bearers: healthy, vigorous and typical of their variety. Mark them early with a ribbon so they are not harvested by mistake. Over the years, this favours traits that work well in your garden.

Seeds must be ripe. Let beans and peas dry on the plant until the pods are brown and papery and the seeds rattle inside. Harvest tomatoes fully ripe. Their seeds sit in a slippery gel; many instructions recommend leaving seeds and gel in a little water for a few days before washing them. Follow established instructions from a specialist book for this.

Then comes drying – the step where most things go wrong. Spread the seeds on paper or a plate in an airy, shady place and let them dry completely. Damp seeds go mouldy in the bag or jar. Better to wait a few days longer than to pack them too early.

Seeds are alive, even while they sleep. Dryness, cool and darkness slow their metabolism and keep them viable for longer. Warmth and moisture make them age faster. So keep them in paper bags or tightly closing jars in a cool, dry and dark place.

Label every bag with the variety and the year of harvest. Without labels, next spring you will no longer know what is in which bag – or how old it is. How long seeds stay viable varies greatly from species to species; specialist books give guidance on this.

Before sowing, do a germination test: put, say, ten seeds on damp kitchen paper, keep it moist and warm and count after a few days how many have sprouted. If eight out of ten sprout, you can sow as normal. If only a few sprout, sow more densely or use fresh seed.

Bought seed is sometimes dressed, meaning treated with agents against fungi or pests. Such seed is often brightly coloured, for example pink, blue or green. It is not meant to be eaten. Store it separately from food, out of reach of children, and wash your hands after sowing.

Only collect seed from wild plants if you have identified the plant with certainty – and even then not to eat it. Some seeds are poisonous, and mix-ups happen easily. This entry deliberately limits itself to familiar garden vegetables.

Passing on, swapping and selling seed may be legally regulated, and this differs from country to country – check local rules. Saving seed for your own garden is generally unproblematic.

“Seed to Seed” by Suzanne Ashworth (Seed Savers Exchange) is considered a standard work on seed saving in the vegetable garden. For many vegetables it describes the type of pollination, isolation needs and storage. Anyone who wants to move on to cross-pollinating crops after their first successes will find the details there.

Your own seed has a special value: over the years it adapts a little to your garden, because you always choose the plants that did well for you. Many old varieties only still exist today because gardeners passed on their seeds.

In a crisis, seed can become scarce. Knowing how to save it yourself makes you more independent. But even without any crisis, seed saving is fascinating – especially for children, who get to see the whole cycle from seed to plant to new seed.