The sexiest plant I have ever seen is perched on a filing cabinet, reproductive parts unabashedly exposed, rouged flesh bedewed with thick, sticky, come-hither nectar. Its petals are waxen to the touch and have the delicate, maroon-to-yellow blush of a Gala apple. This Cypripedium, or Lady's-slipper orchid, is one of more than 300 orchid plants in residence at the Calais Town Clerk's office. Behind the photocopier, an open door leads to a small greenhouse, where the limpid green leaves and thick blossoms of orchids stacked floor-to-ceiling nearly block out the sun.

Eva Morse, 65, has run the Town Clerk's Office from her home for 40 years. Calais recently started construction on an office that will operate independently of Morse's residence. But for now, citizens in search of voter-registration forms and other bureaucratic paperwork are bathed in the perfume of Morse's orchids. What is it about these flowers that provokes such passion? "They're so chiseled and so perfect," Morse sighs. "You almost don't believe they're real."

Morse isn't alone in her "orchidel-irium"; societies have sprung up all over the country for the flower, and there are enough orchidists in Vermont to support three far-flung clubs: The Twin State Orchid Society in Norwich, the Green Mountain Orchid Society in Warren and the one Morse belongs to: the Gardener's Supply Orchid Club in Burlington, where orchidists meet monthly to discuss flower families such as Dendrobia and Cattleyas, and trade tips for growing orchids. At their April meeting this week, orchid-expert Steve Frowine talks about "Growing Orchids without a Greenhouse."

Orchids have enraptured people for thousands of years: The ancient Greeks ate the bulbous roots of the orchis (meaning "testicle") plant to improve their sexual prowess; Chinese emperors and poets saw the orchid as a symbol of nobility and purity -- Confucius called the orchid "the king of fragrant plants." Eighteenth-century Englishmen spent fortunes hunting and collecting wild orchids.

In 1838 the floral fad hit the United States. Until the 20th century, orchid hobbyists were usually wealthy; in 1800 a single plant could cost the modern equivalent of $1000. Reliable artificial germination (introduced in 1917 by Lewis Knudson) and cloning from tissue cultures (1960, Georges Morel) turned orchid growing into a relatively affordable hobby. Today, the price of a single plant hovers between $10 and $40.

No single gateway leads to the orchid habit. Some orchidophiles receive their first flowers as gifts. Others read about the flower in a magazine or attend an orchid show. After their initial orchid experience, aficionados' stories begin to sound the same. One or two plants on the windowsill leads to 20 or 30 under artificial lights, which is replaced by a greenhouse addition accommodating hundreds of plants. No one seems quite able to account for the escalation.

Hope Riehle, 71, of South Burlington bought her first orchid when her son was 2 years old. That son now has children of his own, and Riehle has more than 200 orchids. "When I'm in the greenhouse, I completely lose myself," she admits. Her collection has waxed and waned in the past 30 years -- sometimes dramatically, as when her son shipped 150 plants to her from Thailand -- but more often in plant-by-plant increments. "You can't just buy one; you're hooked," she says. "It's really a disease."

Darrin Norton, 38, owns Mountain Orchids in Ludlow. He describes his current occupation as "a hobby that has gone basically nuts." Norton went into the business to support his own orchid habit. He has been collecting the flowers for 24 years, and breeding and selling them for a decade.

As an orchid wholesaler, Norton is familiar with the variety of orchid hobbyists. People can spend a lifetime pursuing certain shades of pink, he says, or search out orchids that fit their home decor just so, or are of just one species. "You'll have someone after a gigantic plant right next to someone who's fallen for a little twig of a thing an inch-and-a-half tall," he says.

Whatever people's initial reasons for growing orchids, their first success jump-starts a "life-long passion," Norton notes. "Orchids have a deep persona that the public recognizes one way or another. People with very little plant knowledge still recognize orchids. They may not know why, but somewhere in their psyche, they know."

When asked to estimate how many orchids are in his own greenhouse, Norton pauses for a long moment, then offers a rough estimate of 20,000. Orchids are "sort of like potato chips," he says. "You can't have just one, you have to have two. Before you know it, the bag's empty and you're addicted."

Morse started her first orchids on her windowsill, but soon moved them to her porch during the day and brought them into her living room in the evenings. Her porch started out enclosed by screens, which were replaced by plastic, then by glass, until the structure was finally expanded and finished as a 32-by-8-foot greenhouse. Orchids may intimidate growers, Morse observes, but their apparent fragility is misleading. "They're fighters. They're survivors... They seem to thrive on less care rather than more. If I had three I might kill them with kindness. Instead I have 300 and I get to them when I can."

*****

With more than 30,000 species, Orchidacae is the world's largest, oldest and most varied plant family. In the wild they thrive in virtually every imaginable climate: at sea level and 1400 feet above it, underground and in the teeth of 60-mile-per-hour winds. There are orchids in Peru that will only grow on cactuses. Some grow in the ground, but many grow on trees with their roots in the air, absorbing moisture from the ether. Orchidists insist that, despite popular misconception, orchids are neither parasites nor carnivorous. But this is patently untrue: Orchids grow on and consume orchidists.

There is no 12-step program for orchid addicts, but botanical societies let them meet with their fellow sufferers. Horticulturist Anita Nadeau founded the Gardener's Supply Orchid Club in Burlington 14 months ago. Already the GSOC has more than 100 members, many of whom have been collecting for years.

Orchids approach sexual maturity unhurriedly, Nadeau explains. It takes seven years for a plant to blossom for the first time, and thereafter, many bloom just once a year -- some only for a day. It is difficult to imagine doting on a plant for such meager rewards, but these late bloomers' fecundity is fantastic; one orchid seedpod might contain 3 million seeds. And as with sex, anticipation can be a big part of the allure.

To demonstrate the captivating properties of orchids, Nadeau points out one particularly sensuous plant. A Phalaenopsis, or Moth Orchid, is popular with beginners; it does well on windowsills and is not terribly demanding. It is also quite striking, with long sequences of large blossoms on a single spike. This particular plant has eight teacup-sized blossoms dangling from a whip-like stem. Their complexions are porcelain, and with their thick, pouting pink lips, they resemble a gaggle of geisha. Each blossom is full and fleshy, with thick, taut petals begging for a caress. Peering into the brazen heart of these flowers, one starts to get a glimpse of their sway over people.

Most orchids are hermaphrodites, with their male and female procreating parts fused into a single, all-purpose column at the crux of their blossoms. Beyond this physical sexual duality, orchids are powerfully sensual, and flirt heavily with both ends of the sexual spectrum.

Some, like the cattleyas, have meaty, fleshy folds. These captivated painter Georgia O'Keeffe, whose canvasses brim with vulvaic botany. Others, like the Lady's-slipper orchid, have pendulous, unlady-like pouches, immortalized in Robert Mapplethorpe's photographs of their dark, muscular blossoms. Orchids also have lips -- a single distinct petal -- whose aim is to attract pollinating insects, and whose aesthetic affect is often breathtaking. They are an orchid's most ornamental feature, and may have crests, tails, horns, fans or teeth.

The greatest display of the breadth and depth of the orchid family takes place annually at the New York International Orchid Show. With 10,000 orchids on display and attendance figures hovering around 200,000, it offers the grandest display of orchids within reasonable driving distance of Vermont.

Under a tent on the skating rink at Rockefeller Plaza earlier this month, there were orchids with yellow tongues perched on their lips; orchids with velvety petals of deep, stunning fuchsia; orchids whose complex buttery blossoms had shockingly maroon lips; orchids with petals like birthday ribbons. There were orchids with wingspans of a foot and some the size of a Tic-Tac. Some looked like trumpets; some resembled rabbits with bishop hats; some suggested jellyfish; others posed as pinwheels; or looked like beds of butterflies, like sea cucumbers, like bunches of grapes.

The Moth Orchids on display were crisp and luminous, like little moons. Minute Dendrobia with molten blossoms smoldered like beds of coal. Some orchids sparkled like crystals of sugar, while others had the complexion of 40-pound paper or glowed like hot blown glass.

One flower's foliage suggested the coiffure of a monstrous Rapunzel, with thick leaves drooping languidly 5 feet out of its pot. Its blossom was a shapeless, brick-red mess. The crotch of this blossom smelled like fetid meat with a hint of sauerkraut.

The room had a haunting, spicy perfume -- some flowers smelled like cinnamon or lemon-cake, others had no smell at all -- and everyone at the show was bumbling around like drunken bees. It was easy to see how the orchid addiction can escalate. How could you stand to take home just three? Much easier to leave with 300.