Harvesting your own Garden Seeds
Some are easy, some are difficult, and some are better purchased….
Harvesting seeds for next year’s garden in not only possible, but for some flowers, vegetables and herbs, it is so easy that there is little reason to use purchased seeds.
The most satisfying and easiest of all seeds to save are those of the common French marigold. Simply pick the flower heads as they begin to fade, dry the flowers and pull them apart when they are thoroughly dry. The seeds are in the stem pod just at the base of the blossom and one flower will produce enough seed for an entire bed of marigolds.
Not all seeds are so easy to harvest. In the vegetable garden mustard, radish, salad rocket, and Chinese cabbage, all annuals in the cabbage family, as well as spinach, lettuce and the endives, produce seeds readily. In fact, both mustard and rocket will self sow if the seed heads are not harvested immediately when dry.
Let the seed stalk form and cut the entire stalk when it and the attached seed pods are dry and brown. The stalks can be placed in a large paper or plastic bag and beaten lightly with a stick to break the pods. Then pour out the seeds and winnow out the remaining slivers of the pod by blowing lightly over them.
Peas and beans may be left on the vine until the vines turn brown and the seeds are almost completely dry. Shell and dry on screens or in shallow layers in paper bags hung in a dry airy place. Watch carefully for signs of mildew and don’t store them until they are thoroughly dry.
Since peas and beans are both self pollinated, they need little isolation in the garden to prevent crossing. Different varieties of each may be planted for seed in adjacent patches and, by choosing plants just a few rows in for seeds, you can avoid even the slightest danger of crossing.
Since hybrids won’t produce seeds true to variety, only open pollinated corn is suitable for home seed harvesting. Let the corn ripen and the seeds dry on the stalk, then cut and dry thoroughly.
Tomatoes, cucumbers, melons and squash should be left on the vine until overripe. Seeds should then be separated from pulp and washed thoroughly to remove all pulp. Tomato, cucumber and cantaloupe seeds are sometimes easier to clean if they are left to ferment slightly in the pulp at 75º-80º (Fahrenheit) for two days. Wash thoroughly and dry in the sun. Don’t let squash seeds ferment. Although tomatoes are self pollinated, bees will occasionally cross pollinate, so if you are growing different varieties, separate them by 50 feet to keep varieties pure.
Italian tomatoes are even easier to save for seed – simply put overripe tomatoes under hay mulch where you want them to grow next year. In the spring, protect the seedlings until after the last frost.
Cucumbers, watermelon and cantaloupes won’t cross breed, but some squash and pumpkin will, so if you plan to save seeds, plant squash varieties and pumpkins at some distance from each other or stick to one variety of squash and don’t plant pumpkins.
Peppers should not be grown for seed if you plant both sweet and hot varieties unless you can separate them by ¼ mile. Be sure seed peppers ripen thoroughly on the plant.
The biennial crop – beets, turnips, carrots and cabbage – are difficult since they take two years to produce seed. In New England these have to be dug, stored in sand all winter, and replanted in the spring.
To add to the problem, carrots will cross readily with wield carrot (Queen Ann’s lace) which is common all over the area. Beets will cross with Swiss chard, even if it’s two miles away in your neighbor’s garden. Cabbage will cross with cauliflower, Kale kohlrabi, Brussel sprouts, and annual broccoli, producing some very disappointing crops if any at all. These seeds are all best purchased unless they can be grown under highly controlled conditions not available in the average home garden.
It is important to choose the right plant from a vegetable crop for seed production. Getting the seed in not the only aim; getting the best seeds is important if your next year’s crop is to depend on it. From leafy plants such as lettuce, choose seeds from plants that take the longest to go to seed. Conversely, on root plants, choose those with bolt first.
The rule is to save seed from the best plant, not the best fruit. For example, if you have a beautiful specimen of a tomato on an otherwise mediocre plant, serve if for dinner and save seeds from a few less magnificent tomatoes from a healthy plant whose fruit is uniformly good.
Many herbs set viable seeds which are easy to harvest. Since obtaining commercial herbs seed is sometimes more difficult than vegetables seed, and since buying a whole packet for a few plants usually needed is wasteful, herbs are particularly practical subjects for see harvest.
With salad burnet, all chive varieties, dill, fennel, parsley, teasel, and others with large and obvious seed heads, it is just a matter of checking seed heads and cutting them just as the seeds begin to scatter. Place in paper bags and allow to dry thoroughly before storing.
Basil, lemon balm, perilla, and others with less obvious flowers should be watched a little more carefully and flowers stalks removed when seeds are formed. Those with individual flowers like borage and nasturtium should be harvested as flowers fade and seeds form on a one by one basis. These need only be dried a few days before storing.
Seeds of all types of plants should be labeled, sealed in packets, and stored in sealed jars or cans when thoroughly dry. They should be kept both dry and cool. Separate squash, pumpkin and melon seeds from others and check these often for mildew. Discard any bad seed and re-dry remaining seeds if any damaged ones are found.
Storage methods used for seeds you have harvested yourself may also be used to preserve purchased seeds when you have some left over. Very often a packet of seeds will provide many more than the home gardener needs, especially on such crops as salad greens, which produce from the same plants over a season.
If the seeds are kept dry from the time you open the package, unused seeds can be resealed and stored in closed containers just as you would seeds you have harvested. Do not attempt to save carrot, parsnip or beet seeds, however, since they do not remain viable. But properly stored tomato, radish, greens, and herb seeds, along with many others are good for several years.