If you are an average gardener, it's more than likely you have only a modest-size plot of vegetables. Further, you probably have some seed left over. Most gardeners do. While you are apt to save the seed for a while, you will probably toss it out eventually.
Well, you don't have to throw it out at all. You can use that seed next year , the year after that, and maybe even more years in the future.
The answer is in knowing how to store the seed and in knowing its viability, or sprouting potential.
Most seed possesses definite viability beyond the first year. For example:
One year: okra.
Two years: peppers and onions.
Three years: carrots, peas, snap beans, tomatoes, and spinach.
Four years: radishes, beets, cabbage, turnip, cauliflower, and eggplant.
Five years: watermelon, muskmelon, pumpkins, and cucumbers.
Six years: lettuce.
Some home gardeners claim an even longer life for leftover seed. For example , I've heard it said that lettuce will germinate even after 10 years. Seedsmen may argue these points.
If you have any doubt at all about saving seed, get out some of those leftover seeds and test them indoors for germination. Choose those varieties that you sow directly in the ground.
Sprinkle a sampling of seed on a piece of wet flannel or clean turkish toweling. Unused blotting paper works, too. Some gardeners suggest an inverted bowl over the seed to keep in the moisture.
You might even insert some wet paper toweling in a clear glass jar. Then sprinkle some seed on the toweling so that it is visible and you can study it. Cover the jar lightly and watch for the results. You won't put any of these sprouts into the ground, but the test will show you what can be expected to germinate outdoors.
You can also test navy and lima beans in a shallow dish of water.
Roberta Clarkson, in an excellent book on herbs, tells of testing for germination by using a brick set in a pan of water. The top of the brick was kept about two inches above the water level.
If you decide to try this test, then you should follow her directions:
Mark off the top of the brick into sections. Then you can test varieties of seeds by setting 10 of one kind in each section. Invert a box over the top to keep in the moisture and set the brick in a warm place. You can figure the germination percentage by multiplying the number of sprouts by 10.
If you plan to test any leftover tomato and pepper seeds, and any other specimens that you start indoors, you should begin well ahead of planting time -- at least eight weeks before the sprouts are to be set out in the garden.
Now, how should you store those leftover seeds?
Always write the year of purchase on each seed packet. Double-fold the tops of the packets. Then pack them in a clean, empty can that has a tight plastic lid. I further set each can in a plastic bag, twist-tie the top securely, and hang it up in a cool, dark, dry place. Don't forget to label the outside of the can.