Cooks aren't the only ones who create leftovers. Gardeners end up with them, too - frequently, unused seeds.

But keep those seeds around another year or more rather than discarding the pricey packets.

"If you grow very much, you can save money," said Carol Yaw, a veteran gardener and merchandising manager with Charley's Greenhouse and Garden in Mount Vernon, Wash. "I always start with my old seeds before buying new. It's simply a matter of getting quality seeds to startwith. Look to reputable nurseries instead of shopping for discounts."

Seeds from certain crops stay viable longer than others. Samples of the so-called "New Mexico Cave Beans" were successfully germinated after 1,500 years of dormancy.

They did so well that some commercial growers added them to their product lines. "Old seed is fine to plant in most cases by home gardeners," said Bill McDorman, founder and president of the Seeds Trust Inc., in Cornville, Ariz. "You don't get a lower quality plant just because the seed is old. That's a misconception. I routinely get 90 percent- plus germination from tomato seeds that are over 10 years old."

Hard, round seeds seem to last longest, he said. "Generally, onion and chive (seeds) are among the first to die off. But I've planted onion seeds five years old or more and still got many to grow."

B. Rosie Lerner, a consumer horticulturist with Purdue University Extension, has compiled a longevity index for many vegetable and flower seeds. Expect at least a four year life span for beet, cucumber, lettuce, muskmelon, pumpkin, radish, squash, tomato, turnip and watermelon seeds, Lerner said. That same four-year-or-more standard applies to alyssum, calendula, celosia, dianthus, nasturtium, poppy and zinnia, among annual flower seeds, she said.

Still, it would be prudent to do a germination test before dropping any leftover seeds into the ground.

"Take a random sample of 10 or 100 seeds - some number that's easy to remember - and spread them out on a paper towel," said Scott Peterson, owner of Hometown Seeds in Orem, Utah. "Wet the paper towel thoroughly, roll it up with the seeds inside, and put it in an open polyethylene bag that will let the air circulate but not the water. Put it some where warm such as on top of a refrigerator."

Determine the typical germination time from the seed supplier or by searching the Internet, he said. If your test rate is 70 percent or less, then plant more densely, using two to three seeds per hole to get the yields you want.

"This is a great way to increase success in the garden," Peterson said. "It's very discouraging to plant a garden and lose the planting window to poor germination."

Proper storage is crucial to seed viability.

"Keep them as dry as possible, as cold as possible and as dark as possible," Peterson said. "The lower the temperature, the better. Refrigerators or freezers are the best storage areas.

"Keeping seeds over one year is easy. Just keep them out of the sun in a dry place and they will germinate well the next year."

ONLINE Purdue University Extension fact sheet:

http://www.agriculture.purdue.e du/agcomm/newscolumns/archiv es/YGnews

/2009/October/091015YG.html

You can contact Dean Fosdick at deanfosdick(at)netscape.net