How To Save Vegetable Seeds - Part 1

Alright, I’m flat out admitting it: I took on a bit too much the past few days! So in light of our new Growing Challenge Evangelist Edition, I thought I would syndicate an oldie but goodie here. Which reminds me that I never did write a How To Save Vegetable Seeds – Part 2. I’m on it… Next week!

Since those of us in the Northern Hemisphere are beginning to order our seeds and plan our gardens, here is a list of things you need to know about each of your crops if you’re planning to save seeds this year.

Species

This is probably the most important bit of information you need to know when seed saving. Generally speaking, cross-pollination can occur between different plants from the same species.

What confused me in the past was that within a Family, there may be several species. For instance, in the Leguminosae (ie, Legume) Family, there are 12,000 different species. So I can simultaneously grow pigeon peas, runner beans, and lima beans, for example, and save seeds from each of them – they will not cross-pollinate because they are different species! As you can imagine, learning can considerably widen the breadth of what you can plant at the same time.

Pollination Method

Insect-pollinated plants are generally plants that have male and female flowers on the same plant. Squash plants are easy illustrations of this: you have the female flowers that have a mini-squash (“ovary”) at their base, and male flowers that do not. Depending on the species, these crops can be pollinated by honeybees, bumblebees, other bees, moths, butterflies, wasps, flies, and/or hummingbirds.
Self-pollinating plants have male and female flower parts within the same flower – these are called “perfect” flowers (ha, if only we were all so perfect!). Generally you only need one plant to create seeds from these plants. However, some of these are self-incompatible, which means they can only be pollenized by an insect or wind that carries pollen from another plant. And some of these, such as tomatoes and peppers, are greatly aided by wind- and insect-pollination.
Wind-pollinated plants are plants that rely on wind for pollination, such as corn, spinach, and many grains.

All three of these have the potential for cross-pollination. This means if you want to save seeds from these plants, you must isolate them from other plants in the same species.

Isolation

Physical isolation. Isolation distance is the distance a plant needs to be away from another plant of the same species in order to keep from cross-pollinating. However, in many instances you can isolate plants artificially by putting one plant in a greenhouse or wire cage, or covering the flowers with plastic, cloth, or wire mesh. In this case you must hand-pollinate any wind- or insect-pollinating plants.
Temporal isolation. If you want to grow more than one variety, plant the first one as early as you possibly can. When that plant starts to flower, you can sow seeds for the second variety. This works only if the second crop reaches its flowering stage after the first crop has already set its seeds and stopped shedding pollen.

Population Size

Always attempt to grow as many plants as you can in your garden, in order to preserve a wide range of genetic diversity within each crop. If you can only plant a few plants, you can hand-pollinate between your most vigorous plants in order to maintain maximum diversity within your crop. Make sure that when you are saving seeds, you save seeds from several different fruits.

Even if you are selecting for certain characteristics that you’d like to bring out within your next crop, a good rule of thumb is to focus on the plant, not the fruit.

Annual, Biennial, or Perennial

Annuals produce seed within the same year that they are germinated. Once the seed is produced, the mother plant dies.
Biennials produce seed the year after they are germinated. Once the seed is produced, the mother plant dies. These can be the most difficult seeds to save – particularly in the North, as the plants have to be overwintered. Mulch can protect them, but if your area is particularly cold you may have to bring your plant indoors, cover it in a cold frame, or dig, store, and then replant the roots in the spring.
Perennials generally produce seed every year, and live several years before the mother plant dies.

Important Books

How do you learn all of these qualities of your seeds? Read. Read the packets of seeds, read nursery websites, read Master Gardener information, read blogs and forums, read your gardening books, and read seed saving books. It’s an incredible experience to save seeds and grow them the following year, but it’s only incredible if you do it with the knowledge you need!!