LONDON — In a place as obsessed with the past as Britain there is always an anniversary to be celebrated. But this year there is a good 'un. Two hundred and fifty years ago, at Kew Palace on the banks of the Thames at the western edge of London, a "physick" garden was planted by Princess Augusta. The garden was meant to produce herbs that had medicinal uses.
Because of her lineage — Augusta was the granddaughter of King George II and sister of George III — and because of the time in which she lived — the Age of Enlightenment — her little garden soon became a center of plant study. Today, the Royal Botanical Gardens at Kew occupies a 326-acre site; with an annual budget of $55 million for research and conservation, it has become the most important center for plant study and preservation in the world.
It is also one of the nicest days out in London. The variety of plant life boggles the mind even if you have never given a second thought to plants and trees. The greenhouses are always warm and toasty (a big thing on this island). If you time your visit just right, you can get there for the annual open day in the Tropical Nursery, Kew's biggest glasshouse, which consists of 65,000 square feet of space devoted to preserving 1,000 species of endangered plants, more than 40 of which are now extinct in the wild.
Nick Johnson is in charge of "Temperate and Carnivorous" plants, which makes them sound like mild-mannered meat-eaters. He oversees a team of 25. When he talks about his flora it is easy to understand why there is such a strange market for these plants ... a market that threatens their existence.
It's not just rare orchids that are coveted by collectors, according to Johnson. Apparently there are rich plant geeks all over the world who will pay vast sums for plants such as the penguicula, lichen-like growths that appear on a single cliff face in Mexico.
Johnson speaks of his rare penguiculas — which kill their supper, small insects, by secreting a slime that glues bugs to their leaves once they've landed — as well as his rock plants and his cafe marrons — all virtually extinct in the wild — with enormous pleasure. But the question is ... how much damage to the biosphere would the disappearance of most of these plants cause?
"If humankind wants to live in a monoculture, then, fair enough," Johnson said. "But I think most people would prefer greater diversity. How else do you explain the fascination with orchids?"
A visitor to Kew can also see the original "physick garden" in the grounds of Kew Palace (actually the building is not really that big; it's more like a very grand mansion). Professor Monique Simmonds showed me around. At the base of each plant is a plaque with a name and a description of its original use. Melissa offinalis (lemon balm), for example, "drives away Melancholie and Sadnesse."
Simmonds explained that in the 18th century, medicine essentially consisted of whatever could be derived from these plants. About 25 percent of all native British plant species have medicinal properties. Her work carries this study into the modern age. She and her team use a variety of techniques to study plants' healing compounds, "everything from old fashioned mortar and pestles to nuclear magnetic resonance imagery," she said.
One area of study at Kew involves plants from southern Africa that have been used by traditional healers for HIV/AIDS.
Also currently under study in the Kew laboratory is sage, which, according to Simmonds, has properties that may alleviate the worst aspects of Alzheimer's and other forms of dementia.
"The next time I make leg of lamb, I'll be sure to rub extra sage on it," I told her.
To which the good doctor replied, "It has to be the right kind of sage."
"There's more than one kind?" I asked.
"Well, if you use Mexican sage, for example, it has hallucinogenic properties and you will be in for quite a trip." If you want to keep senility away and sanity on hand, Italian sage is the one to rub on your food, according to Simmonds.
More GlobalPost dispatches on gardens:
Full Frame: In a secret garden