The orchid, a family embracing nearly 30,000 species on six continents, is an elegant, louche, large, small, showy and demure flower. It provides us with vanilla, beauty products, prom corsages and traditional Chinese longevity medicines, and, according to Marc Hachadourian of the New York Botanical Garden, it has passed the humble poinsettia to become the world’s most cultivated horticultural crop, both in dollar terms and in sheer numbers. It is also the occasion for “The Orchid Show: Natural Heritage,” the garden’s 20th annual Orchid Show, curated this year by the landscape artist Lily Kwong.

When I opened the door to the Enid A. Haupt Conservatory the other day for the preview, my glasses fogged up immediately: I was stepping into another world. It was a different climate, certainly, hotter and moister than even an unseasonably mild New York February. But it was also a different continent, full of orchids and supporting greenery native to Southeast Asia and China, where Kwong, whose ancestry goes back to Shanghai, looked for inspiration. Orchids are salted all through the conservatory’s ordinary galleries, in pots, clinging to trees, clinging to stones, but the show begins and ends with a pair of ambitious dedicated displays.

The first is a tribute to traditional Chinese landscape painting. In the conservatory’s recently restored Palm Dome, she’s installed two enormous rocks, one larger and slightly overhanging the other, in a small pool. Both are covered with moss and studded with Phalaenopsis in a decorous but eye-catching range of whites and pinks. (Phalaenopsis, also known as moth orchid for the winglike shape of its petals, or the “grocery store orchid,” comes in the most colors, both naturally and thanks to selective breeding.) Closer to the door, two large pots of a pale yellow variety called Fuller’s Sunset offer a handsome complement to the colors of the centerpiece.

Sunlight was falling straight across the display, illuminating a cluster of fuchsia Queen Beer blossoms. Another cluster of Queen Beers perched on the larger rock’s left side, but because it was in shadow, I felt unsure that its duskier and more velvety purple was really the same as the brighter color in the middle. In the same way, the play of light and color created a surprising effect of instability, drawing moss and flowers alike down into the wavering reflections on the water’s surface. (It’s also pretty surprising to see the knobbly shapes and asymmetric harmonies of Chinese ink painting expressed in yellows, eggplant and hot pinks.)

As the show continues through the conservatory’s rainforest and desert galleries, it begins to include orchids from all over the world, and it’s the sheer extent of the flower’s possibilities, more than the beauty or oddity of any one specimen, that knocks you out. There are brown and yellow orchids that could be mistaken for spiders, orchids with purple veins that look like cross-sections of heirloom root vegetables, blossoms the size of a fingertip, and the oversize vegetal funk of the purple and yellow Volcano Queen. There’s a Vandopsis gigantea with coarse, floppy leaves and yellow flower that’s been in the garden’s collection for more than a century; an Odom’s Orange Dream, with strangely serrated petals; and a white Big Lip — so called because the orchid’s usual Jagger-like sneer has been bred out of its bottom petal — which is covered with sensational purple blotches like Rorschach blots.

In a long, windowed hallway, Kwong narrows her focus back to Chinese medicine, lining two narrow pools with austere blossoms, almost all of them white, whose roots are said to have cancer-fighting or antioxidant properties. The monochrome display comes across as a little showy, just because its premise is so obvious. But Kwong also includes a beguiling example of Cymbidium goeringii, a naturally occurring yellowish-green orchid whose diffident little blossom was once a symbol of humility, and whose long, narrow leaves have the élan of graceful brushstrokes.

It’s a trick, in a way, or a feint, because in the final display, Kwong lets the orchid’s paradoxes explode into full view. More than a thousand white, red and patterned blossoms cling to jagged, shoulder-high, moss-covered stones in the conservatory’s seasonal exhibition gallery. (The stones are actually made of polystyrene, but they’re convincing enough if you don’t touch them.) Together they emit a wall of scent, sweet but impassable, that hits you when you open the door, softening you up, so to speak, for the overwhelming visual. Lush but delicate, expensive but incarnating the abundance of nature, anatomically and scientifically intricate but making no special demands of the viewer, the orchid makes a free gift of its sheer, pleasurable beauty.

The Orchid Show: Natural Heritage

Feb. 18 — April 23 at the New York Botanical Garden, 2900 Southern Boulevard, Bronx; 718-817-8700, nybg.org.