If there is anything that illustrates Cornwall's endless capacity to enchant, it is a magical valley near Mevagissey that encloses the Lost Gardens of Heligan. Anyone watching Channel 4's current series will now be familiar with this latterday Sleeping Beauty and how its astonishing vistas are being gradually revealed after 70 years of neglect.
In the latter half of the 18th century, the squire of Heligan drew up plans for a marvellous garden, aided by the most noted horticulturalists of the day. The succeeding generations tended and nurtured it and, at the turn of the century, an intrepid collector, John Tremayne, filled a section of it with palms, tree ferns and bamboos, gathered from his travels to remote locations all over the world.
The First World War took its toll on ground staff and owners alike and what had been one of the foremost gardens in England gradually turned in on itself and grew wild and unchecked behind a wall of impenetrable vegetation. It was not until 1990, and a chance social gathering between the present owner and a group of avid gardeners, that any move was made to investigate the secret landscape behind it.
Tim Smit has been one of the principal architects of its subsequent transformation. He recalls: "We all went to see the gardens and chopped our way through with machetes. No paths were visible; only the tantalising tops of palm-trees hinted at what lay underneath. It was on cutting our way into the big walled garden and seeing a giant vine weaving in and out of the broken panes of glass that we were touched by the romance of the place."
It took a year's preparatory work before restoration of the gardens could begin. "We dreaded finding that most of the plant collection had perished, " says Smit, but "to our amazement, much of the shrub planting remains".
There are several distinct microcosms to Heligan, including the Melon Garden, the Italian Garden and Flora's Green, all of which are beginning to unfurl and blossom under the expert cultivation of Smit and his colleagues. But perhaps the most wondrous aspect of all, is what is fondly described as "The Jungle" - and jungle is exactly what it is.
This is the area that John Tremayne planted with seedlings from his many expeditions. In the sub-tropical climate of this clement valley, they have thrived and there are now 60 varieties of bamboo, and three trees that are among the largest in Europe: Pinus thunbergii, Cedrela sinensis and Podocarpus totara.
Four interlinking ponds add to the spectacle of tropical luxuriance and the valley contains the largest collection of tree ferns in Britain. Unlike a real jungle, it has an air of breathtaking tranquillity and peace, probably as a result of dozing quietly undisturbed for nearly a century. It is a lush and opulent place, where time has stood still and nature is exultant.
As the careful restoration continues, these gardens are maturing into a living testimony to several great plant-collecting expeditions of the 19th and early 20th centuries. Not only have sub-tropical species flourished here but there is also flora from the far East, including a variety of shrubs and trees from Sikkim, Bhutan and Nepal.
These were collected by a friend of Charles Darwin, Sir Joseph Hooker, between 1847 and 1851. Hooker went on to be director of Kew Gardens, but his exotic seedlings remained in Heligan and germinated in this fantastic world within a world.
Heligan also boasts an unrivalled collection of productive gardens, glasshouses and summerhouses, which make it a living, working museum. There are Victorian tools and artefacts as well as vegetable and herb gardens and a manure-heated pineapple pit; lots of mileage in fact for many aspects of the curriculum. And if that was not reason enough, Heligan is also one of the loveliest, most unforgettable gardens you are ever likely to visit.
* The Lost Gardens of Heligan by Tim Smit, a hardback book, is published by Victor Gollancz, Pounds 20 plus Pounds 3 postage; The Lost Gardens of Heligan: A Brief History and Guide costs Pounds 1.50, plus 30p postage; a 24-minute video documentary made by Westcountry Television costs Pounds 8.95, plus Pounds 1.05 postage, all from the mail order department at the gardens. Schools and colleges are asked to contact Wendy Brewin, the education officer, before arranging a visit. The Lost Gardens of Heligan, Pentewan, St Austell, Cornwall PL26 6EN. Tel 01726 844157. Channel 4's series, The Lost Gardens of Heligan, is on Fridays at 8pm until April 18