Cool weather and heavy frost need not put an end to the vegetable garden for this year. Several kinds survive the lower temperatures of fall and even the cold of winter. The cooler weather actually improves the flavor of some of them.

Greens and root crops are the two main crops that can be harvested late in the season - beets, carrots, parsnips, salsify, turnips, rutabages, winter radishes, kale, collards, broccoli, cauliflower, kohlrabi, Chinese cabbage, Brussels sprouts and celeriac, or turnip-rooted celery.

If you don't have some of these vegetables in your garden now, plan to be sure to have them next year.

Brussels sprouts and kale really take the cold. Last January the snow-covered leaves of Brussels sprouts hid a bonanza of firm green sprouts, many frozen almost solid, just asking to be picked.

They had an unsually scrumptious flavor. One suggestion: such sprouts need to be cooked within a few hours after picking or else stored temporarily in a freezer. Being partially forzen in the garden, they tend to get soft an spoil if kept above freezing very long.

Having vegetables in the garden during fall and winter is not really very hard, but a few rules should be followed closely.

First, it's best if the garden is on a gentle slope. This will provide good surface drainage and help safeguard against water-logged soil during heavy rainfall.

Second, the various crops should be mulched with three or four inches of straw to protect them from alternate freezing and thawing.

Third, sowing the seed should be done at the correct time; some vegetables are much more cold-tolerant when mature, but they shouldn't be over-mature.

Beets and carrots usually last well into November in this area without a covering. Parsnips and salsify can take severe freezing weather, and both are improved in flavor by the cold. Turnips and rutabagas are old stand-by winter vegetables, with rutabagas somewhat more cold-resistant. Leeks and chives are both winter-hardy.

Brussels sprouts, kale and collards can take short periods of cold as low as 10degrees F. Cabbage is not as hardy as some of the others: Don't handle heads while they're frozen - wait for a thaw to harvest.

Broccoli, cauliflower, kohlrabi and Chinese cabbage usually yield into December. Spinach, Swiss chard and parsley usually produce until late November. Celeries usually last until early December without protection.