Collecting seeds from your garden

Collecting seeds is an easy way to greatly increase your plant stocks, plus you can swap them with friends to get different plants in return. Seeds you collect from your own garden can be sown as soon as you collect them, increasing your chances of success, plus they are from plants which are already adapted to growing in your garden, so their offspring should settle in better as a result. All in all, collecting your own seed is a much better idea than buying them!

When collecting seeds you should keep in mind that seeds from hybrids may not come true to type, or may not grow at all. So, if you want an exact copy of an existing plant, ensure that you only collect seeds from plants which haven’t been hybridised. However, if you don’t mind a bit of variation, then have a go with any seeds. The cross-pollination of plants (eg in a vegetable plot where you are growing several different varieties of the same vegetable) will result in crossed seeds, so you need to ensure that you are only growing one type in the area if you require results similar to the parent, or simply embrace the diversity!

How you collect seeds will vary depending on the type of fruit containing the seed:

Capsules, siliquas, legumes and follicles (pods)

For example the fruit of Nigella (love in the mist), shown here.

Remove the fruit from the plant when they are ripe but before they open (usually at the point when the pod starts to turn from green to brown or yellow). They should be collected in dry weather to prevent the risk of them staying damp and encouraging fungal infections. Place them in a paper bag, or between sheets of newspaper in a warm room for a few days. They should then open and shed their seeds onto the paper.

Don’t prise any seeds out of the pod which don’t come out readily, they are unlikely to be viable.

Hold the seeds in the palm of your hand and blow on them gently so that any debris blows away, but the seeds remain in your hand (this is a process called ‘winnowing’). Alternatively, sieve the seeds through increasingly small sieves until only the seeds remain.

Samaras (winged fruit)

Remove the fruit from the plant when it is fully ripe. The wings can be left on the seeds or removed to ease handling.

If the fruits are contained in catkins or cones, place them in a paper bag or between sheets of newspaper and keep them warm until the fruits are released.

Achenes (nuts)

Remove from the plant in the green (before it’s ready to fall) or once ripened and ready to fall, depending on each plant’s requirements. This can be done by hand or by placing a sheet underneath the plant and shaking the stem to make the achenes drop. Remove any outer husks, but retain the shell of the nut.

Drupes, berries, pepos, hesperidiums, multiple fruits, pomes and pseudocarps (fleshy fruits)

These should be collected just as they turn from green to their ripe colour, otherwise you might be beaten to them by hungry local wildlife!

With larger fruits (such as apples or peppers) open the fruits and manually extract the seeds. With smaller fruits (such as holly berries or blueberries) place the fruits in a sieve and mash them up while running water over them. Then place the pulp and seeds into a container filled with water. Give it a good shake and allow the contents to settle, then gently pour the pulp and water off through the sieve – the seeds should remain in the jar (unless they are dead seeds, in which case they will be washed out with the pulp). Dry the seeds in paper towels before storing.

If the fruits are quite hard, you can soak them in water to rot away before mashing them up.

With hips (eg from roses) it is easier to to allow the flesh to rot off the seeds than try to remove it by hand. Place the hips apart from each other in a pot of moist sharp sand. Leave it outdoors over the winter keeping it damp (which can also provide the cold stratification required by most of these seeds) then remove them in late winter or early spring – the flesh should fall away from the seeds with ease.

You should always discard any seeds which show any signs of damage, disease, pest infestation, or any other imperfections.