At the time of this writing, you may buy--for $2,000--a rare orchid of impeccable lineage christened Elliotianum Penn Valley, from the genus Paphiopedilum. Unless, of course, Merritt W. Huntington, the manager of Kensington Orchids Inc., has closed the deal on the one plant he has for sale. If that is the case, you'll have to wait five years or more before another Elliotianum Penn Valley becomes available.

If money is no object, you could go to Wynnewood, Pa., and drop in on Dr. W. W. Wilson, a psychiatrist with an orchid business on the side. He has the only other Elliotianum Penn Valley in the country. His price is $4,000.

With green stripes on unusually long white petals and a bronze-maroon pouch, Elliotianum Penn Valley is a beauty that has won the highest horticultural awards of the land. But it happens to be a slow grower. No one can be sure how many years will pass before a new stalk appears and its rhizome--a fleshy root indispensable for independence--can be separated from the mother stock and repotted.

Another slow grower--known as Winston Churchill Indomitable-- was ordered by a Californian in 1969 and delivered last spring. For choice orchids, people pay the fullCharles Fenyvesi is a staff writer for The Washington Post Magazine. Orchids, from page 29 amount in advance--the Californian paid $750 back in '69 for his Winston Churchill.

Of the 67 "finest Paphiopedilums" listed for sale by Kensington Orchids, one of the largest orchid nurseries in the United States, 21 are sold out. The prices of these orchids start at $25, but most range from $200 to $300. Ordinary orchids can be purchased in a two-inch pot for as little as $4.

To orchid fanciers, the prices do not seem high. Like antique dealers, they sell and barter the orchids they grow; as investments they buy superior orchids which they can then cross and cross again. With luck and patience, one of their new hybrids may win a prize, and along with the glory comes a higher price for its divisions.

Since 1856, when the first human- pollinated orchid flowered, London's Royal Horticultural Society--the Vatican of orchid growers--has registered more than 75,000 such hybrids. As with royalty and horses, orchid pedigrees are recorded with meticulous attention to detail. Every five years, the Royal Horticultural Society publishes a stud book--a directory unintelligible to the layman.

The pedigree on one of Huntington's plants can be traced to 1913, and he has dozens going back to the 1920s. Most of his orchids are divisions of divisions of divisions, with genealogies as long as the Bible's list of who begat whom.

The plants are sliced apart with razor-sharp shears sterilized with a propane torch. New hybrids are created by transferring the pollen of one plant to another plant using the sharp point of a pencil, and then raising plants from the seeds. Growing a plant from seed to bloom requires five to seven years.

Most orchid species come from the rain forests of the Amazon and the Congo, from Central America and Southeast Asia. Orchids mimic the wasps, spiders, scorpions and macaws of their habitats; their raw yellows and hot pinks speak of the morning of Creation. Yet their shapes are the refined fantasies of Baroque, Rococo and Art Nouveau, and when domesticated for boudoirs and mantelpieces, they compete with the finest crystal and porcelain.

Their scents range from lily-of-the- valley innocence to sensuous musk, from subtle vanilla to rotting apple.

Braided and ruffled, stippled and mottled, delicate and sinister, their variety is astonishing to botanists. In the wild there is seldom a colony of them, and it is a fairy-tale wonderment to spot an orchid reigning in splendid isolation on a tree trunk.

Orchids are the royalty of flowering flora. They have no use for something as base as soil; they need only air and moisture. Transplanting in soil killed many of them in the l9th century, when orchids were a rage in the civilized world, and enthusiasts and businessmen scoured every leafy wilderness to capture specimens never before seen in Europe. The potting medium that growers eventually developed is a mix of fir bark, redwood chips and peat moss. The ratio depends on the particular orchid.

For orchid growers, life is a succession of beauty contests. Last month, for instance, state and regional orchid societies held 11 shows in the United States. Judges, who must pass a test to prove they are not colorblind, evaluate entries on the basis of excellence in form, color and characteristics such as "habit and arrangement of inflorescence." The score sheet awards points on sepals, petals and labellum--parts of the bloom--but does not list scent, regarded as more intangible than beauty.

To win an award, the new hybrid must be superior to its parents. The highest honor, given by the Royal Horticultural Society as well as by the American Orchid Society, is a first-class certificate, which goes to about half a dozen orchids a year. Other awards include the Certificate of Botanical Merit, the Certificate of Cultural Merit and the Judges' Commendation. Plants propagated from a winner carry their pedigrees on tags attached to their containers. A hybrid of unknown parents is worthless.

Some growers look for new colors, such as bronzes, oranges and the darkest purples. Though many have tried, no one has yet produced a fire- engine red orchid; the closest color is fuchsia. "We'd be pleased with a reasonably red orchid," says Huntington, his blue eyes twinkling. He dismisses as "technically impossible" the creation of a black orchid, so popular with writers of mysteries and comic strips.

At 56, Huntington is muscular and loquacious, stocky and cheerful--across between farmer and scientist, salesman and hobbyist. He loves to talk about orchids, and he moves about with the alacrity of a man half his age. He started working with orchids in eighth grade, some 36 years ago in Springfield, N.J., where a teacher talked him into taking 10 hours of horticulture a week, instead of language. He then attended Rutgers University and worked in its greenhouses.

During World War II, Huntington enlisted in the Maritime Service after he was rejected by the Navy because of poor eyesight. After the war, he didn't go back for his college degree, but got married and worked for seven years at Lager and Hurrell, the oldest orchid company in the United States. When that firm went out of business, he ran an orchid nursery on Long Island. In 1964, he became the manager of Kensington Orchids, Inc., which had been established in the 1930s by physician Edgar M. McPeak.

Huntington now owns a little less than half of the corporation. He finds Kensington an ideal location for orchids such as cymbidiums and certain types of cattleyas. "Florida is hot all the time, and the West Coast doesn't have the humidity," he says. "Here the drawback is December and January. But everywhere you have one period that's not ideal."

He supplies flower shops with cut cattleyas used for corsages. Customers for his potted orchids include a service station attendant from Rockville and a college mathematics professor who comes over from Pittsburgh several times a year; stylish single women of all ages and a couple in their 30s with only a few pieces of furniture but a fine collection of orchids; heirs and heiresses in chauffeured Rolls Royces, and a teen-ager in a 20-year- old Volkswagen who experiments with $4 seedlings and hopes to win an award one day.

Huntington says many orchid fanciers are millionaires, but "they are no different from those who don't know where their next $10 for a plant will come from. There are plenty of people who simply give awayn divisions to those who can't afford to buy them. Money doesn't matter. I have lots of friends who are rich, and others who are garage mechanics. We don't care how they live and what they've got. We are all regular people when it comes to orchid society meetings.

"We have plenty of doctors and lawyers among our customers. Orchid growing is a form of escape. Professional people who work hard all day long and their work is sometimes messy need a hobby to make them forget.

"But you have to be scientifically inclined. We are experimenting all the time. We try new mixes to grow orchids in, we try new techniques of growing, and of course we develop new hybrids."

Huntington says most orchid growers are religious. "How can you grow plants if you are not a believer?" he says. "You can't help thinking about what created all that out there. When you work with things that grow, you have a sense of Creation. He is helping us."

Every year some 500 of the 20,000 members of the American Orchid Society go on collecting trips to places such as Venezuela, Thailand and Australia. For the majority, guided tours take busloads to view collections and to examine natural habitats off highways. But an intrepid few penetrate jungles in Thailand and Zaire. A Florida travel agent special- izing in orchid tours is organizing the first group expedition to New Guinea--dangerous for humans but a paradise for orchids, many yet unidentified.

"I don't like tramping in the woods," Huntington says. "I pollinate in my greenhouse, rather than look for those orchids God created."

Orchid growers, the gilt-edged elite among gardeners, are worshipers of excess. Whether they risk their lives in search for rare specimens in jungles or contemplate their treasures in the sanctuary of their greenhouses, their goal is to increase and to improve nature's bounty, to devise new varieties, to create more beauty of ever greater complexity.

For Huntington, orchids are both a business and a hobby. "It's a 24-hour job," he says. His wife Helen collects orchid memorabilia, and their otherwise ordinary suburban home is filled with orchids and their likenesses in sculptures of gold, glass and stainless steel, on ceramic plates and needlepointed canvases, in photographs, paintings and lithographs. Orchids are etched onto cocktail glasses, enameled on medallions and printed on bedsheets.

"People think we are nuts," Huntington says, without apologizing.

"I don't grow orchids but I look for orchid stuff wherever I go," Helen Huntington says. "I am an orchid wife."

Three of their four sons also grow orchids. The eldest, tall, red-bearded Tom, is 30 and works in the nursery full time. "Orchids are extremely complex," he says. "I am never bored working with them. I grew up with orchids, but I find that there is always more to learn about them. The complexity fascinates me. It is incredible how an orchid evolves a system to attract insects for pollination--not just a scent but tunnels and ledges and spurs, even trigger mechanisms."

Will he work with orchids for the rest of his life? "Oh yes, I think so," Tom says. "I hope so."

"Working with orchids may not be the best-paid job, but it is most satisfying," says Clive Atyeo, 43, an employe who divides orchids and repots them. English-born Atyeo lives with his wife and their three children on the farm. He has worked at Kensington Orchids since 1966, and has some 800 orchids of his own in his basement. "I have made a few crosses," he says, "and I've got some promising crosses coming up, but nothing great. Not so far." What's so special about orchids? "Orchids are intriguing."

Merritt Huntington says business has picked up a bit under the Reagan administration. Vice President George Bush's wife Barbara is an orchid grower and has been to his nursery. Huntington says that the reason more orchids are sold now is that there are more fancy parties. And what is a fancy party withoho simply give awayn ut orchids?

A few orchids grow in the ground--in the Blue Ridge Mountains, on both sides of the river at Great Falls, even in Rock Creek Park. But their demands for soil and moisture are fussy, and they can survive only in their own microclimates. Even experts have problems transplanting them.

Huntington says his nursery has about 100,000 plants in eight greenhouses, kept warm last year by $30,000 worth of heating oil. He used to burn 50,000 gallons a year, but last spring he put two layers of polyethylene sheeting over the glass.

The temperature must be between 70 and 75 degrees during the day, and 60 at night. A sudden frost can kill Huntington's assets overnight, so the nursery has two backup heating systems as well as an electric generator in case of a power failure.

The nursery has seven employes working on 11 acres. Three-fourths of an acre is under glass.

Huntington's home is 200 yards from the furnace room. Though he has an alarm system, on cold winter nights he gets up several times to check if the heat is on and the air pumps are working.

Last year, Kensington Orchids grossed $300,000. "Actually, we didn't make any money," Huntington says. "Our profit is in our inventory. You don't make much money in this business, but we are happy working with orchids."

When attention is paid to their special needs of temperature variation, high humidity, and the right amount and the right kind of light, orchids do as well in greenhouses, bathrooms and even offices as in their natural habitats. But it helps to have that magic quality known as a green thumb.

If properly pampered, orchids flower once a year. A single plant may offer at one time as many as 12 perfect blooms which sometimes last as long as three months, then wilt suddenly, gone in a day or two-- still gloriously complex and intriguingly beautiful even when dead. CAPTION: Picture 1, Merritt Huntington holds one of his "children," Laeliocattleya Chevy Chase, born in 1965. In foreground the proud parents: L.C. Bob Gore, bred in the United States in 1954, and C. Labiata, a native of Brazil; Picture 2, clones, or meristems, of Brassolaeliocattleya Malworth Orchidglade; Picture 3, the roots of orchids do not require soil, but get their moisture from the air's humidity; Picture 4, Cattleya Carol Ackerson hangs from its parent plant, flanked on either side by masses of Cattleya roots; Picture 5, Huntington holds Paphiopedilum Elliotianum Penn Valley, an orchid of impeccable lineage, bred at Kensington Orchids. Its price tag? $2,000. If this one's sold, Huntington will have no more for five years. You could get one from Wynnewod, Pa., but there they're $4,000. Picture 6, jars of seedlings that were germinated at a lab and then returned to the nursery. The seedlings are numbered for identification purposes. Orchid-breeders do not name hybrids until they bloom, seven years from now for these seidlings; Picture 7, A Laeiocatlaya hybid bred atKensington Orchids flaunts hues of lemon and salmon. PHOTOS BY SUSAN MCELHINNEY; Susan McElhinney is a Washington area free-lance photographer