A couple of years ago at the Westonbirt Festival, Stephen Wenlock made a sunken garden traversed by irregular concrete stepping stones across a sea of Verbena bonariensis. The surfaces were flecked with embedded rusting nails and that is important; one of the beauties of concrete is that, depending on the hardness of the mix, it erodes to reveal the shapes and patterns of its constituent aggregates. It also proves, however, that there is more to making good use of concrete than simply mixing sand and cement; it takes planning and the right recipe.

Concrete can of course be used vertically as well as horizontally. In Cleve West’s Chelsea garden for Saga Insurance there are vertical sculpture panels of concrete, fractured horizontally to create a diagonal line, the top and bottom sections clinging together by their reinforcing bars. You could have made them from stone or stainless steel, but what’s the point? The whole object of them is to use the tension of a casting.

West says, “I thought it would be just like casting some outsize concrete slabs. I could not have been more wrong. Once you start thinking about colour and texture there is far more to consider.” He is right, of course: at previous Chelseas there has been work by David Undery, an artist specialising in thin burnished concrete panels which are extraordinarily sophisticated. West has also commissioned some huge concrete bowls which will be a complete contrast for their integrity and sophistication. Between them the bowls and the panels will really show what concrete can do.

Also at Chelsea this year, Xanthe White’s garden for New Zealand Tourism will show huge scattered shards of black-painted concrete representing the eroding mountains of New Zeal­and breaking up towards the sea. Stuart Perry is using lime-washed concrete, in varying widths and forms, to create the bold vertical framework of the Halifax “These Four Walls” garden. Barnett and Nixon’s Modernist garden for Savills is contained by a sculptural relief wall, partly clad in wood, partly indented with rectangular depressions, made of rendered blockwork. There is also a glamorous, polished concrete path – literally buffed and waxed.

At the Chaumont Festival of Gardens last year, in the Loire valley, there was a remarkably beautiful concrete wall. It had been made by pouring the concrete into the space between wood­en walls of shuttering. What made it special was the fact that domestic waste had been layered into the concrete as it was pour­ed – glass, crushed cans and other materials. The finished effect was a kind of geological cross-section of modern civilisation. Also at Chaumont was a mounded “beach” of pebbles set up and populated with an Easter Island-like colony of rising oblongs, some in concrete, some in wood and some in steel, with a scattered planting of grey tamarisks and bamboos dotted between. It was ravishing and just the sort of thing you could use in a domestic garden.

Win Tickets to the Show

We have three pairs of tickets for the final day of the Chelsea Flower Show, Saturday May 27, and a chance to meet Stuart Perry, designer of the Halifax “These Four Walls” show garden. For a chance to win tickets, answer the following question on www.timesonline.co.uk/times promo, and enter code no X4616 :

What colour are the walls in the Halifax “These Four Walls” show garden?

Competition open to UK and RoI readers only, over 18 years. One entry per household. Entry is not available to staff of News International Ltd and Halifax plc. The prize will be awarded to the first three correct entries drawn after the closing date and the winner will be informed by phone. There is no cash alternative. The closing date is midday on Monday May 22, 2006 and tickets will be sent by recorded delivery.

Explore Gardens

• Chelsea Flower Show

• Hampton Court Palace Flower Show

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