An herb garden can be attractive but the main reason for growing herbs is to use them to season foods. Their leaves, fragrant sees, fruits, buds, barks and roots have been used for this purpose since ancient times.

During the past few years there has been a big increase in growing herbs in the garden. Most herbs are normally imported from temperate and tropical countries throughout the world and the price of prepared herbs has increased. In addition, freshly prepared herbs from the garden offer more of the natural flavor than those on the shelf at the store.

Since herbs are used in small quantity, only a few plants of the most promising herbs are needed.

Cultural practices are similar to those for most vegetables. Most seed companies that sell herb seeds or plants provide full directions on the package for planting.

Thyme and sweet marjoram are attractive as hanging plants near a sun window year-round. Sweet basil, a must for all Italian dishes, and caraway, delicious for cooking in goulash, also grow well indoors and provide decorative, delicate blossoms.

There are many larb herb gardens throughout the country open to the public, such as the ones are the National Arboretum here, Callaway Gardens in Pine Mountain, Ga., and Brooklyn Botanic Garden, Brooklyn, N.Y.

"People who come to our herb garden learn how easy it is to grow their own herbs at home," says Gordn Tyrrell, assistant director of horticulture at Calloway Gardens. "They ask questions, get ideas and go home and develop their own garden."

Choosing herbs is strictly a matter of personal taste, according to specialists at Northup King Co., 1500 Jackson St. NE, Minneapolis, Minn. 55413, which offers 18 varieties of herbs in seed packets to the customer. Many of them can be easily grown indoors.

Today's growing concern that "you are what you eat" finds many people checking their sodium inta,e on their own or on the advice of the family doctor. Herbs offer an option to seasoning with salt, often completely replacing it.

The flavor of fresh vegetables is greatly enhanced by herbs. Rosemary adds an exciting touch to carrots, summer savory is perfect with snap beans and sour cream with fresh-snipped chives for baked potatoes is unbeatable. Canned or frozen vegetables come to life with a touch of the right herbs, especially if substituted for salt in the cooking liquid.

Beef and poultry, commonly laden with salt during cooking, are much more delicious when cooked with a few fresh mushrooms and chopped green pepper or onions, with an added dash of sage for beef and a sprig of parsley for chicken. English thyme is excellent for meat gravies and dressing, but a little goes a long way with the pronounced flavor of this herb.

Flavorful herbs instead of salt are ideal to use in homemade soups. Chopped dill used sparingly in soup and stew has a distinctive flavor, as piquant as salt but far more interesting. Chervil is famous for the flavor that it adds to soups and sauces.

"Canning, Freezing & Drying," by the Editors of Sunset Books and Sunset Magazine (Lane Publishing Co., Menlo Park, Calif., 128 printed pages, well illustrated, $4.95, paperback can be ordered direct).

There's no special magic to canning, according to the authors. Fruits, begetables, or meats are packed into canning jars, which are fitted with self-sealing lids and then heated. Sustained high heat kills dangerous organism that could cause food spoilage in the jars; it also causes the gases in the food and in the jars to expand, driving out most of the air left inside. Hot jams, jellies and other preserves are cooked first and then packed, hot, into hot jars.

"It's very important to use the right equipment when you can," they write: "everything from the canning jars to the right kettle is crucial.

"A canning kettle is needed to process acid foods, such as fruit, tomatoes and some pickles. Any kettle large enough for the jars to be completely immersed and fully surrounded by hot water is acceptable.

"A steam canner, recently reintroduced on the market, is an alternative to a canning kettle for processing acid foods such as fruit (it cannot be used to replace a steam pressure canner).

"Safety is crucial in canning. In general, there are two basic methods of canning -- the water bath method and the steam pressure method.

"The water bath method can be used safely with fruit, tomatoes and pickles. Jars full of these acid fods are heated in a hot water bath, using the canning kettle or steam canner. The simmer hot (180 to 190 degrees F water) provides enough heat to destroy the organisms that might cause spoilage in these foods.

"The steam pressure method must be used when canning all other vegetables (low-acid vegetables), meat, poultry and fish. All of these foods are processed in jars under high pressure in the steam pressure."

"Drought Gardening," by Sue Hakala (Garden yway, Inc., Dept. B126, Charlotte, VT 05445, 32 pages illustrated, $1.50, paperback, if ordered direct add 60 cents postage and handling).

Most vegetables require about an inch of water for a healthy growth, according to the author. But even in a dry year you can have a successful garden, she writes. That is what this booklet is all about.

"Locating your garden in an area where part receives the morning sun and afternoon shade will helpt o keep moisture in the soil. The garden should receive at least six hours of direct sunlight a day. Cool-weather crops, such as tomatoes or sweet corn. $99 [text omitted]

"We can rate vegetables by the amount of water they require over a season for healthy growth: less than 12 inches of water, beets, turnips; over 20 inches of water, tomatoes, potatoes, celery.

"Most seed packages will tell you to space your plants in a single row. In a dry season, we strongly urge you to use wide-row planting. Space between rows can allow for irrigation furrows, if necessary."