Perhaps the most praised member of the bean family is the soybean.

"Highly nutritious" and "a great meat substitute" are some of the more common references to it. Some folks go so far as to call it "the incredible bean." There is good reason for this.

As soy meal, it enhances stock feeds to a considerable degree, and, as soy flour, it does similar things when included in the baked goods we humans eat. As soy chips or flakes it often is included in granola-type cereals. It is the basic ingredient, too, of textured vegetable protein, the stuff that brings a meatlike taste and feel to vegetable dishes.

In China, the soybean is processed into virtually all the fresh milk consumed in that country. And when a yogurt-like culture is added, this same soy milk becomes tofu.

The bean also is delicious when served up on the dinner plate as a shelled green dish. Leftovers can be served cold with a sauce of your choosing. It also adds substance as well as flavor to a beef stew.

For these latter reasons, then, it is good to know that the soybean recently has qualified as a backyard vegetable crop. I grew some on an experimental basis last year and found them as simple to cultivate and about as productive as conventional bush beans.

For decades soybeans had been regarded as a commerical agricultural crop only. But, conscious of its value, breeders began working on the little bean to produce a varity that was edible in its green state as are lima beans. What they came up with is a quickly maturing plant that produces ready-to-eat green shell beans approximately 75 days from planting.

Such rapid reproduction makes a soybean patch possible even in areas of short summers.

The bushes grow about 22 inches tall and bear clusters of small pods along the main stem. I found these beans difficult to shell in their green state but since have learned of a simple shelling method from Ted Torrey, a vegetable breeder with the W. Atlee Burpee Seed Co.

"Put the beans in boiling water for a few minutes then drain," he said. "You will find the beans pop out of the shell with just a little finger pressure." When cooked, the beans are a bright green, looking attractive as they are tasty.

If you can't eat all your soybeans in the green stage, leave the pods on the plant to dry. If heavy frosts threaten, cut the plants off at the base and haul them into a shed or garage to dry further. When fully dry the beans are easily shelled. Store the dry beans in a screw-top jar or tightly tied plastic bag. Prepare and bake dry soybeans as you would dried lima beans.

When the soil has warmed up nicely, sow soybeans in soft soil between 1 and 2 inches deep. Plant 2 to 3 inches apart in rows about 18 inches apart. Otherwise, sow the seed in broad rows between 6 and 8 inches apart in every direction.

Once up and growing, mulch between the young plants with 2 to more inches of hay, straw, shredded leaves or even wood chips. This mulch virtually eliminates weed growth and keeping the soil moist at all times. Water once a week in dry weather.

A legume innoculant applied to the seed as planting time provides the colonies of bacteria that will attach themselves to the plant's roots, enabling it to feed off "free" atmospheric nitrogen.

Edible soybean seeds are available from several mail-order seed houses, among them: W. Atlee Burpee Seed Co., Warminister, Pa. 18991, or Riverside, Calif. 91502; and Thompson & Morgan, Inc., Box 100, Farmingdale, N.J. 07727.