A fall and winter vegetable garden may be the best yet.

The first frost need not put an end to the season. You can keep on harvesting from the garden through autumn and even into winter. Hardy vegetables that thrive in cool weather are the ones to plant. There is a big selection to choose from, and they usually taste better.

In fact, many specialists believe vegetables harvested in the fall are actually better suited for canning and freezing since they develop more slowly under early fall growing conditions and are tastier and more tender.

Bush snap beans are everyone's favorite but it's often feast or famine - too many beans all at once and none later. It is easy to spread the harvest. Plant a row now, of green or yellow, or better yet, both.

One important point: Check the number of days to maturity for the varieties you're planting - it is in the seed catalog - and count back from the average fall frost date for your area.

Burpee's Tenderpod, for example, takes 50 days from seed planting to first harvest. That means if you plant Aug. 1 you should have the first harvest about mid-September.

Of course, you can fudge a little on the dates and many times it pays off.

Leaf lettuce, radishes and spinach are fine fall crops. All stand some frost in the garden, and if grown in a cold frame can be harvested well into winter.

Green peas from the garden are a spring taste-treat and they are just as good in the fall. Pods develop well in cool autumn weather and plants take light frost but not a heavy freeze. Try Sweetpod or Dwarf Gray Sugar snow pea types, as well as regular shell varieties such as Blue Bantam, Green Arrow and Wando.

Broccoli, Brussels sprouts and cauliflower are grand in the fall garden. An easy way to start them is to sow the seed now in a specially prepared seedbed or corner of the garden. When the seedlings have a couple pairs of leaves, transplant them to the permanent location. Green Comet Hybrid broccoli is ready to harvest in about six weeks from set plants. Brussels sprouts and kale really take cold weather and you can keep on picking them into winter. Fall and winter cabbage, red and green, are easy to grow from seed planted now. They keep well and are fresh and tasty into late winter.

Winter Bloomsdale spinach is so hardy it will live over the winter and be ready to supply uou with fresh, tasty greens next spring.

Turnips and retabagas are old standby winter vegetables with rutabagas somewhat more cold-resistant. Leeks and chives are of the onion family and both are winter hardy.

There is one thing to remember with summer planting: Keep the ground evenly moist. Weather is often hot, dry and windy, so water as necessary with a fine spray to keep the soil damp until the seedlings are up and growing well.

It sometimes helps to cool lettuce seed in the refrigerator 2 or 3 days before planting, to help them sprout.

Plant your fall and winter garden on a gentle slope if you can. This will provide good surface drainage and help safeguard against waterlogged soil during heavy rainfall.