Garden by the sea in London SW3

GREEN shoots have acquired a bad name recently, though through no fault of their own. No one now can write a celebratory essay on the arrival of spring, the leafing-up of trees, the surging growth of rosebuds, without the ghostly image of Norman Lamont looming up behind the emerging greenness and pouring metaphorical weedkiller on it.

But despite the Treasury's attempts at sabotage, May remains an extraordinary month. You would have thought after three or four decades of the same conjuring trick, you would have got used to it, like the rabbit coming out of the hat. Somehow, you don't.

Perhaps we don't because we dare not. Perhaps deep down there is still a panic that the green might never come out of the grey and the brown again. When it does come, we are not only relieved but grateful, for spring is one of the few things we are still allowed to feel good about.

Beltane was the old way of celebrating May's rebirth, a Celtic feast of fire, sacrifice and general mayhem. Now we have the Chelsea Flower Show with the immaculately pinstriped Robin Herbert, president of the Royal Horticultural Society and chairman of Leopold Joseph Holdings plc, as our elegant Green Man.

The show is an anachronistic triumph. No one sitting down today to plan a mammoth event of this nature would think it possible, logistically, for it to take place in London SW3. There is a vast marquee and there are gardens to be put together (23 this year, including a prize-winning seaside garden built on 20 imported tons of sand). The majority of the exhibits are growing plants with specific needs by way of food and drink not nearly as easily available in Chelsea as Big Macs and halves of lager.

Part of the magic of Chelsea is the excitement that surrounds all ephemeral, tented events: the sudden transformation of the setting, the atavistic lure of an itinerant life for those whose futures are firmly shackled to the 8.05 from Woking, the particular quality of light as it filters through canvas, the smell of crushed grass.

You can get that at any county agricultural show, but Chelsea's strangeness lies in the fact that all this happens slap bang in the middle of the most densely populated city in Britain. All these pulsating, growing, flowering things suddenly arrive in the middle of a place generally marked out by tarmac, concrete, tin and barrenness.

The most important thing that marks Chelsea out from other horticultural shows is the standard of the plant and garden exhibits. A lawn-mower stand looks much the same anywhere, but you will rarely see a display of carnivorous plants or lupins such as Marston Exotics and Woodfield Brothers put on in the Great Marquee anywhere except Chelsea.

There is a delicate balance to be kept in any large horticultural show between exhibits that are there because they bring in money, those that push forward into new horticultural or design territory, others that are there for spectacle and those that relate directly to most people's experience of gardening.

Since it was set up, the RHS has considered it an important part of its role to educate the public. This is an unfashionable thing to do now. Fortunately, the society, magnificently impervious to fashion, has continued to give Chelsea a firm underpinning of educational displays.

You can find these along the western side of the Great Marquee. Here the British Beekeepers Association will tell you all you need to know about bees in your garden. The Friends of the Royal Botanic Gardens will enlighten you on Kew's programme for the conservation of plants and the Institute of Horticulture may persuade you to 'come out' as a gardener.

There are certainly factions who consider these stands a waste of space and who would gladly trade Harlow Carr's Story of Rhubarb or Pershore Horticultural College's Aspects of Earthworms for another lush conservatory, kitted out Southfork-style with every accessory that a fevered interior designer could dream of. Except conservatory plants. These are generally ousted in favour of cane furniture and cushions.

The conservatories hover round the central marquee at Chelsea hissing 'lifestyle, glamour' at the prim educational exhibits inside. Were the Chelsea Flower Show put on for entirely commercial reasons, conservatories would have ousted earthworms long ago. Fortunately it is not.

In the larger equation between plants and sundries, plants win hands down. The Chelsea Flower Show is primarily about green, growing things, not hardware and this is surely an important part of its success. It is a celebration, not a marketing opportunity.

News International, which mounted a new gardening show at Wembley over Easter this year, seemed to look at things the other way around. This may have been one of the reasons that the show failed so spectacularly to draw the expected crowds. As a venue for people who like gardening, Wembley anyway has all the allure of an unmanned railway station on a November night. It is about as glum a site as can be imagined but, with enough green inside, this initial impression might have been overcome. Unfortunately, the green was scattered as thinly as on a slug-ridden seedbed.

Chelsea is not everyone's cup of Thea sinensis. Few disagree on the magnificence of the plant displays in the Great Marquee - Dibley's streptocarpus, Hazeldene's violas, Mattock's roses, Southfield's cacti - but the show gardens arouse deeply divided emotions.

The top award at Chelsea is the Fiskar's Sword of Excellence, given to the best garden in the show. This year it was won by a wild flower and seaside garden, designed by Julie Toll, built by Hasmead (Landscapes) and sponsored by Countryside Wildflowers and John Chambers' Wild Flower Seeds. It sits, a small lost piece of Norfolk dune, on the corner of the showground's Main Avenue.

'Rolling sand dunes set the scene,' explains the show catalogue, 'in this almost forgotten part of a large garden descending to the seashore. A rocky outcrop on the seaward side and the windswept yellow dunes host very little vegetation. Amid the more stable grey dunes is a brackish pool providing a habitat for wet-loving plants. Native trees and shrubs are growing on the dune heath and wild flowers flourish in the short, rabbit-grazed turf.'

This, of course, is in every way a politically correct exhibit, but is rabbit-grazed turf what gardeners seek above all else in their gardens? Are we panting for brackish pools? Should we not be fighting harder to protect and support proper wild places, rather than trying to recreate the Dune Experience and other carefully tweaked habitats in our gardens? Rise up gardeners and prepare to defend your petunias. The mind police will soon have us all growing the lesser pond sedge.