   Saving Seeds - November 1, 2000 Jeff Schalau, County Director, Agent, Agriculture & Natural Resources Arizona Cooperative Extension, Yavapai County After the peak vegetable and flower season and before composting the remnants of these once productive plants, consider harvesting some seeds for next year's crops. Before starting, you will need a brief understanding of pollination biology and follow a few simple guidelines. Once you start saving seeds, you can save money on new seed each year, share your seed harvest with friends, and gain an appreciation of how our ancestors grew their favorite crops each year. When saving seeds, a viable population must be maintained. A population of individuals comprises a gene pool. To maintain the genetic diversity inherent in a population, it is important to grow an adequate number of individuals when reproducing a variety. That is, five plants do not contain enough genetic diversity to capture and maintain the breadth of genetic diversity to sustain a viable population. Given your garden area, you may decide to save seeds for a select number of crops to maintain some genetic diversity. Only healthy vigorous plants should be saved for seed. Pollination mechanisms for plants are normally divided into two categories: self-pollinated types and cross-pollinated types. Self-pollinating crops have perfect flowers (both male and female parts in the same flower), and they will usually pollinate themselves before opening. This will usually insure their "self" pollination. Cross-pollinated crops are naturally crossed by either insect-borne or wind-borne pollen. Therefore, isolation distances between different varieties of the same crop are crucial to insure varietal purity. Insect pollinated species should be separated by at least one-quarter mile with some type of physical barrier. The barrier can be a screen cage that excludes the pollinating insect or a natural barrier such as a forest, hills, etc. Different varieties of peppers should be separated by 500 feet to avoid cross-pollination. Melons, pumpkins, cucumbers, and squash need even more personal space - at least a half-mile. Wind pollinated crops, such as corn, cannot be easily isolated using barriers and require a distance of at least one mile between varieties to maintain purity. Biennials require more work and commitment, as they do not send up seed stalks until the second season. Biennials include beets, Brussels sprouts, cabbage, carrots, cauliflower, celery, onions, parsley, parsnips, rutabaga, Swiss chard, and turnips. Leave hybrid seed production to the seed companies unless you really know what you are doing. Seeds from hybrids produce a mix of offspring, which may have different characteristics than the parents'. Seed from hybrid vine crops are often quite variable, also squashes, cucumbers, melons, and pumpkins often cross-pollinate with other genetically compatible varieties. Unless pollination has been strictly controlled, strange hybrids often result. Among the vegetable seeds most easily saved are non-hybrid tomato, pepper, bean, cucumbers, and summer squash. Collect seeds from fully mature, ripe fruit of these plants. Some tips follow for each of these crops. Tomatoes: The seeds are encased in a gelatinous coating, which prevents them from sprouting inside the tomato. Remove this coating by fermenting it. This mimics the natural rotting of the fruit and has the added bonus of killing seedborne tomato disease. Squeeze the seeds from a fully ripe fruit into a bowl, add water, and let stand at room temperature for about three days. Once fermentation occurs, mold will form on the surface of the water. Add more water, stir, and then gently scrape mold and debris off the top. Repeat until only clean seed remains, and then strain, rinse, and leave the seeds at room temperature until dry. Peppers: Select a mature pepper, preferably one that is completely red. Cut the pepper open, scrape the seeds onto a plate, and let the seeds dry in a nonhumid, shaded place, testing them occasionally until they break rather than bend. Leave at room temperature until completely dry. Beans and Peas: Beans, peas, and other legumes: Leave pods on the plant until they are "rattle dry." Summer squash: Summer squash is at the seed-saving stage when you cannot dent the squash with a fingernail. Cut it open, scrape the seeds into a bowl, and then wash, drain, and dry them. Store most saved seed in airtight jars. The exception is legumes, which store best in breathable bags. To keep the seeds dry, fill a small cloth bag with about one-half cup dried powdered milk. Place the packet in the jar beneath the seed packets. Label your container with the variety, date, and other information. Store your seeds in a cool, dark, dry place; a refrigerator is a good choice. Avoid opening the container until you are ready to plant. Stored seeds will retain their viability for different lengths of time. Melon seed can be stored for as long as five years, while sweet corn is only good for one year. Other types of seed remain viable for two to three years. The University of Arizona Cooperative Extension has publications and information on vegetable gardening and composting. If you have other gardening questions, call the Master Gardener line in the Cottonwood office at 646-9113 or E-mail us at mgardener@kachina.net and be sure to include your address and phone number. The Yavapai County Cooperative Extension web site is http://ag.arizona.edu/yavapai/. |