A ROUND-THE-CLOCK guard is in place to protect the secret site of one of the world's rarest flowers, growing wild in the region for the first time in decades.

The only example of the Lady's Slipper Orchid in Britain has flowered for the first time this summer - after 11 years of painstaking care.

And it is hoped hundreds of tiny seeds released as a result may now grow into new examples of a variety once prized so highly by Victorian collectors that it was driven to extinction.

But the threat remains even today. With a single flower still worth thousands on the black market, countryside watchdog English Nature has vowed to maintain a vigil to protect the plant, which is believed to be growing somewhere in North Yorkshire.

Plant expert Ian Taylor says secrecy is vital if the precious bloom is to stand a chance.

"The orchid actually bloomed as long ago as June, but we've kept that quiet until now as those in the know may have used the information as a clue to its possible location.

"But it was a major milestone after more than a decade of work and we hope the next step is to have some young plants appearing."

But it is not just human predators who could put the project in jeopardy - orchids have other natural enemies, including slugs, snails, voles and rabbits.

Mr Taylor is determined to succeed. ''They are such stunning flowers - different, exotic, sometimes sinister, sometimes beautiful," he said.

"It's almost as if they don't belong in the British countryside but somewhere else like the Tropics. But they are here and their rarity is like a precious jewel."