By Sarah Browning, Extension Educator in Lancaster County
Mid- to late-summer is a good time to start the process of saving seeds for next year’s garden. Growing and harvesting your own seeds isn’t as hard as you might think. However, before you get started, there are a few important things to keep in mind when selecting plants from which to save seeds.
AVOID HYBRID PLANTS
Many, if not most, of the vegetable seeds and transplants you purchase at the garden store in spring are hybrid plants, developed through the crossing of two distinct parent lines. Hybrid plants are bred for their vigorous nature and improved disease resistance. They often have fruits that are more uniform in size, shape, color, have better storage quality and shipping ability. For tomatoes, improved shipping ability usually means the tomato flesh is firmer than that found in most heirloom tomatoes. However, hybrid plants do not grow 'true-to-type' from seed, so aren’t good candidates for seed saving.
Choose instead to save seed from open pollinated heirloom plants or naturally occurring plant species like red veined sorrel, Rumex sanguineus, which will grow 'true-to-type' from seed each time. Seeds can be saved from ornamental plants too, like four o'clocks, nasturtium and marigolds.
The next consideration is how to collect the seeds? This depends on how seeds are produced by the plant — either as dry seeds or wet seeds within a fruit. Harvest seeds from your healthiest, most vigorous plants.
DRY SEEDS
Many plants produce seeds in a dry seed head, such as lettuce or dill. To harvest lettuce, allow a few plants to mature and develop flower heads. Allow the flower heads to mature until seed stalks develop a fluffy dandelion appearance, just before the seeds are completely dried. Seeds will fall off the stalk and be lost if allowed to totally dry on the plant. To harvest dill, cut the seed stalks when the seeds are fully sized and turning brown.
Bundle the stems together with rubber bands or string. The seed heads can be placed inside a paper bag as they dry to catch any seeds that fall. Hang the bundles to dry in a warm, well-ventilated location. Dry the harvested stalks until the seeds can be shaken or rubbed from the stems.
Allow bean or pea pods to turn brown on the plant. Harvest the pods and dry them for 1-2 weeks. Shell them and they are ready for storage.
Peppers should be allowed to mature about two weeks past their best edible stage. Harvest the fruits, cut them open, remove the seeds and allow them to dry for a few days. When the seeds are dry and can snap in two, they are ready for storage.
WET SEEDS
Pick fruit from desirable plants when ripe. Cut fruit and squeeze out the pulp into a container. Add a little water, shake the mixture well and let the pulp ferment 2-4 days at room temperature, stirring occasionally. When seeds settle to the bottom of the container, pour off the pulp at the top of the container. If necessary, add more water and let any remaining pulp ferment again. When you have mostly seeds remaining, pour them into a fine sieve. Rinse them well and spread them in a thin layer on a piece of netting or screen, allowing them to dry thoroughly.
SEED STORAGE
The first rule of seed storage is correct temperature and humidity. After seeds are harvested and dried, they need a cold, dry environment for storage, ideally around 35°F. Seeds keep for a long time at these temperatures. Dryness is important; if too much moisture is present, seeds will swell and sprout, or rot.
Where is the ideal storage spot? An air-tight container in the refrigerator is a good location. A shelf in the garage, basement or laundry room is not a good location; it gets too damp or hot at times during the year.
FOR MORE INFORMATION
To find more information on storing seeds, please see Nebraska Extension NebGuide "Vegetable Garden Seed Storage and Germination Requirements," (G2090) http://go.unl.edu/seedstorage.