How to save your own seed for beginners

As we begin to near the end of the growing season, I am starting to make a conscious effort to start saving some of my own seeds. Saving your own seed is a great practice that can save you a lot of money. It is also more sustainable than buying seed and you get seed that is fresher and better adapted to your local climate. There are so many benefits to saving your own seed, although it is not always as simple and straight forwards as it seems. Some seeds are definitely easier to save than others, and some seeds you cannot save at all.

Open pollinated vs hybrid

You may have come across the terms ‘open-pollinated’ and ‘hybrid’ before when looking at seeds. There is a crucial difference between the two. It is completely fine to save seeds from open-pollinated varieties. You cannot save seed from hybrid varieties, which are usually labelled as F1, or less commonly F2. I mean, of course you technically can save seed from hybrid varieties, and something will grow. But it will not be the same as the plant you saved seed from, and instead it will revert to one of it’s ‘parent’ plants. It will be a complete luck of the draw on what you may get, although it will likely be something that is less desirable than the original plant. For more information on F1 seeds, see my previous blog post here.

Annual vs biennial

Some plants germinate and produce seed all in one season. For other plants, they may not produce seed until their second year. This is often the case for root crops, such as carrots, onions and parsnips. As a general rule of thumb, it is usually easier to save seed from crops that grow and produce seed all in their first season.

Cross-pollination

Cross pollination is another issue to be aware of. If plants cross-pollinate, then you may end up with seeds that grow into something that is not true to type. The seeds may have traits from different varieties that have cross-pollinated with one another. It is generally easier to save seed from plants that are self-fertile. Plants that require pollination by insects or wind are usually more likely to cross. A prime example of this is brassicas, where you need at least 20 plants from a single variety to save good, strong seed, and they can cross pollinate if within 1500m of another flowering brassica.

Isolation and hand pollination

One way around avoiding cross pollination is through isolating flowers and hand pollinating them. This can be a great method for crops such as tomatoes, peppers and squashes. This is obviously a much more involved way of saving seed, but if you want to save seed that you can be confident is true to type, it is the best way.

Choosing plants to save seed from

When saving seeds from plants, you want seeds with the best genetics. Remove any plants that bolt early, and choose the strongest plants to save seed from. Once you have chosen your strongest plant(s), choose the best sized and looking fruit to save the seed from.

Beware of toxic squash syndrome

If you are growing in your back garden and have only one type of squash, its seed is far more likely to come true to type. If you are growing on an allotment, cross pollination is a greater risk. It can also be fun to save squash seeds regardless, and see what you end up with. Of course, you only want to experiment this way if you have the space to grow extra plants. One word of caution – be extremely careful when saving seed from squashes and courgettes. They can sometimes be toxic, which can potentially be fatal. Always taste a small amount of the fruit first before cooking. If it tastes bitter, ditch it. The toxic compound in the squash has an extremely bitter taste.

Tomatoes

Tomatoes are a great crop to save seeds from. However, many people think that you can just save the seed without isolating the flowers. Whilst this is true, there is an element of risk when it comes to cross pollination. Some varieties are more likely to cross pollinate than others though, depending on the structure of the flower, and if the stigma sticks out of the flower or not. As a general rule of thumb, beefsteak tomatoes and potato leaved varieties are more likely to cross pollinate than say, a regular salad tomato or a cherry tomato.

To improve the viability of your tomato seeds, it is also good practice to ferment them for a few days in their own flesh. Scoop out the seed cavity into a dish and just leave it on the side for 3-5 days depending on temperature. This helps to replicate the process that happens in nature, where the tomatoes will rot down on the ground and leave the seeds behind. If there is not much of the jelly-like flesh then add a little bit of water, no more than an equal amount to the flesh. Let the mixture start to go mouldy, then give the seeds a good wash and leave them out to dry before storing. This process helps break down the coating around the seed to improve germination.

Legumes

It is easy to save seed from beans and peas. If you’ve got some that have got a bit big then just leave them be and let them continue to grow and hopefully you’ll still have some time to save seed. You want to ensure that the pods are brown and papery for saving seed. Leave them out for a week or two after harvesting, to ensure they are fully dry.

Peas and French beans are self-fertile and are less likely to cross-pollinate than runner beans or broad beans. If you are growing more than one variety, it is still good practice to try and have them a few metres apart if you wish to save seed. You can of course save seed from runner beans and broad beans, but just be aware that over time they are more likely not to be true to type.

Flowers

It is also incredibly easy to save seed from many flowers. When a plant flowers, it is trying to produce seed to complete its lifecycle. This is why the process of deadheading will usually encourage the plant to put out more flowers. By leaving a few flowers to go over towards the end of the season and letting them completely dry you can then harvest the seed.

A few of the easiest to save seeds from are calendula, cosmos, marigolds, nasturtium and sweet peas. Unharvested flower seeds will also grow where they fall the following season – so if you want to grow the same flowers in the same place, you could just let the seed heads go over and self-seed. This saves time on both ends of the season! One thing to be wary of however, is that flowers may cross pollinate too. So if you want specific colours/varieties then this method may not be for you. Personally, I’m quite happy for my flowers to cross pollinate more than I am for my vegetable crops.

Community seed saving

Saving seed can be so easy and it is such a satisfying thing to do. It is also a great way to pass on varieties you love to friends and family. Whilst seeds are generally not too expensive, it is something that very quickly adds up – particularly if you want to grow many varieties of the same vegetable! Seed saving is a great way to continue growing your favourite varieties whilst also having the budget to try more new ones the following season. I also love the idea of setting up a seed saving club – where each person saves seeds from different plants. This way you will have plenty of seed to go around, while only having to save a few seeds yourself. You may never have to buy seeds again!