The first step in seed-saving is to let your plants produce the seed. Choose the very best example of each type of plant as the parent for the next generation. Look for good color, fine flavor, superior size, texture, or yield, and disease or insect resistance. In short, choose plants with unique qualities that set them apart from the rest. Never collect seed from diseased plants, because some diseases are seed-borne. Growing conditions during seed development affect the quality of seeds, so take good care of the expectant plants. To set seed, the plant must be pollinated. Some plants, such as beans, lettuce, peas, and tomatoes are self-pollinating, which means the flowers on the plant produce and accept their own pollen. Others require pollen from a second plant, delivered either by the breeze or the bees. This can complicate seed-saving when related plants cross-pollinate, thereby affecting the seed crop.
In the garden, usually only plants of the same species can cross-pollinate. If you grow several varieties of a species, cover selected plants, or individual flowers, to prevent cross-pollination. For wind-pollinated crops, such as beets, chard, corn, and spinach, use muslin or spun-bonded polypropylene to keep away the tiny grains of pollen. For insect-pollinated crops, such as broccoli, carrots, or squash, cheesecloth will keep the bugs away from the flowers.
Once you cover plants that are normally pollinated by insects, you become responsible for their pollination. They can be hand-pollinated by gently stroking flowers with a fine artist's paintbrush.
The process becomes simpler if you grow only one variety of each plant, or if you don't mind the effects of crossing two cultivars.
Often a cross between two types, say of tomatoes or carrots, doesn't result in any tremendous surprises. But let two cultivars of the species Cucurbita pepopumpkins, zucchini, scallop, crooknecks, acorn squash, spaghetti squash, and some gourdsmingle, and you could find some real oddballs in next year's pumpkin patch.
Compared to the overall cost of gardening, seed is really a bargain. But why pay for them when they are all around you for free? If you have plants, you have seeds. You should know, however, that seeds from hybrid plants don't produce plants just like their parents. Hybrids are the result of cross-fertilization between two or more species. Open-pollinated plants, on the other hand, are fertilized naturally"in the open"and are likely to produce offspring similar to the parent plant. If you plan to collect seed for future seasons' plantings, you will have better results if you choose seeds or plants that are labelled "open-pollinated" or ''OP" in a catalog or nursery. 