The world of the orchid

Generations of botanists and florists seduced by the orchid's natural beauty have long known there is something special about the "supermodel of the plant world". Now, the history of the floral pin-up will need to be re-written; a new discovery suggests that orchids bloomed when dinosaurs roamed the earth – far earlier than previously thought. A team of American scientists in the Dominican Republic found, perfectly preserved in a lump of amber, grains of orchid pollen attached to the wings of a 20-million-year-old bee. Until now, plant historians were forced to rely on scant fossil records to chart the origins of the plant, but the new find, detailed last month in the science journal Nature, suggests that orchids arose as long as 85 million years ago.

The naming of names

The orchid, or orchidaceae, family gets its name from the Greek orchis, which means testicle, a reference to the plants suggestively-shaped bulbous roots. "Orchis" first appeared in a natural history book by Theophrastos, the ancient Greek "father of botany". The orchid family is the largest and most diverse of the flowering-plant kingdom, with more than 25,000 species observed so far. Each year, as many as 300 new species are added to the list and some scientists estimate that more than 5,000 orchids remain undiscovered. A further 100,000 hybrids have been cultivated by dedicated horticulturalists.

Orchids are grouped according to the way they retrieve their nutrients. Most are perennial epiphytes, which put out roots on other plants, mostly trees. Lithophytes grow on rocks, deriving nutrients from the air, rain and even their own dead tissue, while terrestrial plants grow in soil.

Hardy Perennials

While they might look fragile, orchids are very tough and have evolved to thrive in all but aquatic and desert habitats, and on all continents except Antarctica. Schomburgkia tibicinis is a rock-dwelling orchid with flower stems that rise up to three metres in height in order to attract pollinators. The plant also supports armies of ants in its hollow bulbs, where the insects defend the plant against leaf-eating pests and herbivores in exchange for nectar. The Australian species Rhizanthella gardneri is fertilised underground, where it lives and flowers, never seeing the light of day.

Sex and the species

Eighty-six per cent of orchids are pollinated by insects; others are fertilised by bats or birds. Cymbidium sports a yellow beacon that appears to offer parcels of tasty pollen to pollinating bees. While they struggle to chew the decoy treat, the orchid deposits the real pollen on the insects' backs. The bumblebee orchid (Ophrys bombyliflora) has evolved to look and smell so like a female bee that males attempt to mate with it. It isn't only bees and botanists that have been seduced by the orchid. The male crestless gardener bowerbird of New Guinea decorates the entrance to its nest with orchid blossoms.

Alternative medicine

The ancient Chinese were among the first to use orchids in medicine. They considered them to be aristocrats among plants, their perfume thought to symbolise virtue and wisdom. The philosopher Confucius once said, "The association with a superior person is like entering a hall of orchids." The writings of Englishman John Parkinson in 1640 showed that orchids were among the drugs dispensed in London to cure conditions as diverse as fever, swellings and sores.

Orchids have also long been held to possess powerful aphrodisiac properties. One ancient Greek philosopher reported that the ground root of a species, named after the fertility god Priapus, allowed a man to perform 70 consecutive acts of sexual intercourse. Tempted by the perhaps improbable claims, optimistic lotharios almost ate the plant to extinction. In his book, Theatrum Botanicum, Parkinson wrote: "If a man ate a large orchid tuber, he would begat many children." But the 17th-century English botanist Nicholas Culpeper warned against over-indulgence. Writing in the British Herbal, he said: "The roots are to be used with discretion... they... provoke lust exceedingly which the dried and withered roots do restrain."

Charles Darwin

The evolutionary theorist and orchid enthusiast was ridiculed by his fellow naturalist Thomas Huxley when he correctly described how Catasetum saccatum launches its viscid pollen sac in the direction of insects. Many also doubted him when he predicted that there would exist a moth with a proboscis long enough to penetrate the 30cm nectar-producing spur of Angraecum sesquipedale (also known as Darwin's orchid), which is impenetrable to other insects. Twenty years later, scientists discovered the hawkmoth whose appendage was a perfect fit.

Big Business

Orchid dealers and collectors spend millions every year on exotic species, and the worldwide retail business is estimated to be worth in excess of £2.5bn. The largest recorded payment for a single plant was £1,500 in 1890 – equivalent to almost £100,000 today. In the Netherlands, buyers at auctions hand over £37m each year for cultivated moth orchids alone.

According to a survey by the UK's Flowers and Plants Association, orchids are the most popular houseplant in the UK. Most cut orchids, which can survive up to six weeks in water, are imported from Taiwan, the Netherlands, and Thailand. Taiwan is the world's biggest exporter of orchids and is home to a state-of-the-art, 200-acre orchid plantation. The country hosts an international orchid show, where many growers display species from the Phalaenopsis family.

The Hunters

When the British naturalist William Swainson sent a box home from Rio de Janeiro in 1818, Victorian London was astounded by the orchids he had used as packing material. The plant, called Cattleya labiata after the botanist who rescued it, William Cattley, was brought to flower and did much to trigger a mania for ever-more exotic specimens. Many nurseries sent orchid hunters on years-long missions to collect plants from remote jungles and mountain ranges.

In the mid-19th century, the Prague-born hunter Benedict Roezl toured the world in his quest to collect more than 800 species of orchid. Today, over 40 plants bear his name. At around the same time, the botanist John Day devoted his life's work to the plants, creating a series of more than 50 scrapbooks containing nearly 3,000 exquisitely detailed drawings and watercolours. Orchid hunting is still big business. In 2001, a team in the Peruvian Amazon jungle discovered a new species (Phragmipedium kovachii) whose stunning purple flowers caused a sensation in the orchid fraternity, making headlines in The New York Times. Soon, specimens were being smuggled out of Peru, and changing hands among unscrupulous dealers for tens of thousands of dollars.

Food for thought

Vanilla is a rare example of an orchid used for food. The seeds and pulp found in vanilla pods are used to make vanilla extract, most of which is produced in Madagascar. The island churned out three million tons of the stuff in 2005, much of it destined for Coca-Cola – the US drinks maker is the world's biggest consumer of vanilla extract.

In Turkey, an ice cream made from salep (flour produced from the tubers of dried wild orchids) is so popular that trade is threatening the plants' future; a thousand orchids are required to make every kilo. The dessert is called salepi dondurma (fox-testicle ice cream).