Tip of the Week: Collecting seeds

Posted in Gardening Tips on November 8 2010, by Sonia Uyterhoeven

Sonia Uyterhoeven is Gardener for Public Education. Join her each weekend for home gardening demonstrations on a variety of topics in the Home Gardening Center.

By this time of year, you probably have begun saving seeds of your favorite annuals and vegetables. Seed saving is fairly straight forward as long as you follow a few simple rules.

When collecting seeds in your garden, look for healthy plants that possess the characteristics you desire. If you have a pot marigold (Calendula) with a pale apricot color that you admire, collect seeds from the paler specimens to try and keep the nice shade. You will always get variation, but you are participating in the selection process as, in essence, an amateur breeder.

Many of your flowers and vegetables are cross-pollinated, Mother Nature’s way of passing along diversity. If you want the seeds to be pure, isolate the plant (generally by building a cage or covering for it) or pollinate by hand, but this is generally only necessary for commercial growers or for seed-saving enterprises.

Most important is to always choose healthy plants so that you end up with healthy, viable seeds. Don’t waste your time collecting seeds from F1 hybrids. They will never come true to seed, and you will get some strange results. Heirloom varieties, on the other hand, tend to be fairly stable and are wonderful to collect.

Gather seeds from your garden once the flower or vegetable has started to ripen. With flowers, the seed heads will start to turn brown. Cut off the seed heads and collect in plastic containers or paper bags.

At this stage two things are important. One is to make sure you label everything as you go. If you wait until you can spread everything out on the living room table to identify, you will be give yourself an unnecessary headache. Record the collection date and the cultivar name.

The second essential thing to do is to be careful not to collect immature seeds. Many seeds will continue to ripen as they dry, but if you collect them before they have completely formed, they will not mature and produce viable seed. They should be fully formed and starting to dry. With fruits and vegetables, the fruits should be just starting to get over-ripe.

Seeds have different dispersal mechanisms. Many seeds are catapulted into the air or the inflorescence (the seed head) shatters to help the seeds disperse effectively in the wild. These seeds should be harvested just before they are ripe so that they are easier to collect; otherwise, they will explode as you try to remove them. Place the inflorescence in a small paper bag and cut the stem.

Remember to harvest your seeds on a dry day—you will dry them anyway before you store them, so it helps to get a head start and to ensure they don’t rot during the process.

Some collected seeds require no cleaning or minimal cleaning. Other seeds have chaff or are in fleshy fruits, so it is important to clean off these seeds so they will germinate properly. Next week we will take a look at how to clean, dry, and store seeds.