Seed Saving
If you want to save seed, there are a few basics. The very first rule is that the plants have to be Open-Pollinated (designated OP in the catalogs). Hybrids are a mix of all kinds of ancestors, and won’t breed true, almost always reverting back to a less desirable parent.
If you have no intention of saving the seed of certain kinds of vegetables, it doesn’t matter how many kinds or varieties you plant, or how close you plant them. Cross-pollination only affects the next generation, not the fruit or root you’ll be eating.
Some crops cross-pollinate more easily than others. In a small garden, the easiest way to ensure purity is to grow only one variety of any species at a time, and hope a nearby neighbor isn’t, either. Next best is growing them as far apart as you can, or planting other kinds of plants between them.
A good seed catalog can provide a lot of information (Territorial Seed has a good one.) You’re mostly interested in the Genus, Species and Variety. For a cabbage, the Genus is Brassica, the Species is oleracea, and one variety is
‘Savoy Perfection’ (single quotes): Brassica oleracea ‘Savoy Perfection’. If the first two names of one kind are the same as another (Brassica oleracea), the plants may cross. If they are different, they are not likely to cross.
Corn is the only vegetable (it’s really a grass) where cross-pollination affects the first crop (the silk is the closest thing to its flower, the tassels provide the pollen, and the corn kernels are the seeds). If your sweet corn is cross-pollinated by field corn or popcorn upwind, the blandness of the corn you’re eating ten days later will be noticeable, and the saved seed would be inferior also.
Squashes, Pumpkins & Gourds consist of five different species. They will cross within the same species, but won’t usually cross between the species in nature. So, if you wanted to grow one variety of each species, you should be able to grow them all in one yard and still get pure seed.
* Cucurbita pepo: Pumpkins, acorn squash, spaghetti squash, zucchini, yellow crookneck summer squash, scallop/patty pan squash, delicates, vegetable gourds, and small, hardshell gourds (yellow-flowered).
* Cucurbita moschata: Butternut squash, Long Island cheese squashes, Dickinson and Kentucky field pumpkins, Seminole pumpkin, Neck pumpkin, Calabaza.
* Cucurbita maxima: Buttercup squash, Banana squash, Hubbard squash, Kabocha squash, Lakota squash, Arikara squash.
* Cucurbita mixta: Green-striped Cushaw (aka Kershaw)
* Cucurbita ficifolia: Shark-fin melon
(Note: none of the squashes will cross with the white-flowered hardshell gourds))
All of the Brassica oleracea (cabbage, kale, cauliflower, broccoli, brussel sprouts) will cross with each other, but not all the others in the family will. Check the species name (the one following ‘Brassica’), if any are the same they may cross, but if they’re different, they won’t. Weeds with the same species name can cross with the domestic one.
Melons will cross with each other, but nothing else. Ditto for cucumbers.
Beans and peas drop their pollen and self-pollinate the evening before the flowers open, so the pollen is not very available to pollinating insects. Two feet between bush types is usually enough if you’re not selling the seed or keeping heirlooms pure. Pole types are a bit more promiscuous, and should be separated by more space, by different types of plants, or adjacent varieties should be very different so you will see a hybrid the following year and yank it before it flowers..
Lettuce is generally self-pollinating, but if you want to keep the strains separate, you’d best plant them 12-25 ft apart, or grow different vegetables between them. But keep its ancestor, the weed called prickly lettuce from flowering, or it could cross with your domestic lettuce.
Tomatoes, eggplant and peppers don’t cross among themselves, and are self-pollinating, but if you plant different varieties at least ten feet apart, there shouldn’t be any crossing.
Carrots will cross with each other and the wild weed called Queen Anne’s Lace, which is a carrot ancestor, if they are within 1000 feet of each other. The weed crosses are easy enough to weed out when you harvest the roots: they’re thin, white and tough.
COLLECTING SEED
1) Mark a couple fruits from several plants (12 is not too many, the more separate plant sources, the better and healthier the diversity of genes). Colored surveyor's tape is good. Warn your family not to pick any of the marked fruits.
2) Let the marked fruits mature. Tomatoes, peppers, zucchini, cucumbers (etc) will be past their prime and softening. Leave winter squashes on the vine either until the vines wither or a serious frost threatens.
3) Fruits with seeds trapped inside are obviously easier to collect than those that are released from small pods. Collect tomatoes, peppers, cucumbers, squashes, melons, gourds, okra and tomatillos when they are very mature. Immature seeds won’t sprout, ever. Cut them open and collect the seeds. Some will be dark (like watermelon) and some will be very light or white (cucumbers, melons). The easiest way to dry them so they don’t rot or mold is to put them in open containers or paper bags with their species and varieties written on them. Shake them and stir them up every day, so they dry evenly.
Tomatoes are a little different, as they have a coating that prevents sprouting, and you’ll have to remove it by fermentation (and it helps kill any bacteria, too). Squeeze the seeds out of the tomato or scrape them out with a spoon into a quart jar. Add just as much water as you have seed pulp and stir. Put the jar in a place where you won’t notice the unpleasant smell for three days. Don’t worry about the mold that forms, it’s part of the process. On the third day, scrape off the mold and stir the rest of the contents. Spoon or pour off all the yucky stuff on the top, including any floating seeds (they’re no good if they float), and save the seeds that are sitting on the bottom of the jar. After you’ve poured out most of the junk, add more water to the bottom seeds and stir again. Pour off anything that floats. Repeat until all you have in the jar is clear water and seeds sitting on the bottom. Pour through a strainer, and then dump the seeds onto a glass plate or cake pan and stir a couple of times a day to help them dry. Some people spread them out on paper towels instead, and let them stick to the towel as it dries out. When they are thoroughly dry, they just roll or fold the paper towel and put it in a labeled paper envelope for storage, and tear them apart when they plant them next year. Otherwise, keep stirring them around on the plate until they’re dry and mostly separated.
3) Smaller seeds like parsley, carrots and dill will need to be watched carefully, and harvested when they are fairly dry. If you think you might forget and they’ll fall to the ground, you can make simple cloth (polyester organdy or similar fabric allows air in and dries quickly after rain or watering) drawstring bags to put over the seed heads as they are maturing, pull the string snugly around the base of the flower and tie in a bow. When they’re dry and crisp, just cut the heads off the stems with the bags still on, and collect them in a large bowl. Remove the bags and tap out the loose seeds when you’re out of the wind. Be sure to mark the kind and variety of seeds that they are.
4) Let pea pods and beans dry on the vine. Then collect them on a dry day into an open container and let them dry even more out of the weather. Remove from the pods when they are dry and crisp, and store in marked paper bags.
5) Some seeds are at the base of the dried flowers, like sunflowers, artichoke and cardoon. Cut the dry heads off and rub or pull the dry center of the flowers off. The seeds are embedded in the base of the flower. Remove and dry.
6) Seeds must be carefully stored to retain their viability. Store them in marked paper bags or envelopes, which will allow them to dry out more if they need it. Plastic bags contribute to molding and rot if they aren’t dry enough. Keep cool and dry. Heat and moisture will decrease their viability considerably. Some people store their seeds in a freezer, but if the seeds are too moist, it will kill the embryo. A refrigerator is a better place, or a cool basement.
7) Carrots, cabbage, parsnips, leeks, onions, celery, beets, turnips, kohlrabi and salsify are biennials. They produce their crop one year and their seeds the next spring, and then they die. Here is some info for cold climates, as you will have to make some effort to keep them alive through the winter for them to flower the next year:
http://www.cog.ca/documents/Savingseedsofbiennialvegetables.pdfMost of these have umbel-type flowers, and cloth bags may be the easiest way to collect the largest amount of seeds. If you try to harvest them when they are green, they will not be viable and won’t sprout.
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