Why is garden design of such current interest, transcending disciplines? Not just landscape architects but architects and artists compete to be involved. For instance, Chateau Chaumont on the River Loire is now holding its ninth International Garden Festival; in Switzerland, Lausanne is staging a second 'Jardins dans la Ville'; and in Rome 'Le Jardin 2000' has opened in the grounds of the sixteenth-century Villa Medici, since 1803 the home of the French Academy.
'Le Jardin 2000' is the last in a series of three exhibitions at the villa, after 'La Ville' in 1998 and 'La Memoire' in 1999, all curated by Laurence Bosse and Carolyn Christov-Bakargiev with Hans Ulrich Obrist - Koolhaas' collaborator for the Hayward's 'Cities on the Move' show and responsible for the Soane Museum's recent flirtation with contemporary art, 'Retrace Your Steps: Remember Tomorrow'.More than 30 artists and architects are involved, with established names (Zaha Hadid, Dan Graham, Daniel Buren) alongside the less well-known, including several who are on yearlong residencies at the Academy.
The 7ha gardens of the Villa Medici were laid out in the late sixteenth century, and that Renaissance template is still in place. There are three major areas: an open piazzale immediately in front of the villa's garden facade; a series of square, hedge-surrounded enclosures to the north; and to the south, off a raised terrace, the Bosco - a wooded zone culminating in a steep flight of steps which leads to a belvedere with wide views over Rome. But, overlaying the Renaissance diagram, are later, Romantic elements - primarily the tall umbrella pines whose profiles now seem so integral to the garden's appearance. A further, speculative dimension comes with the site's history in Ancient Roman times.
Surprisingly few of the participants in 'Le Jardin 2000' respond directly to the archaeological nature of the Medici gardens, their evolution over time. As Obrist remarks: 'Many of the works here are not particularly site-specific. They're in 'rooms' that are much like museum spaces, with green hedges replacing the white walls.'
The parameters which determine the exhibition are indicated by two contributions in the catalogue - Obrist's own, and that of the French landscape architect Gilles Clement.Obrist supplies a 900-item alphabetical list of conceptual gardens, each with its one-word character: 'Decoy Garden, Delirious Garden, Desert Garden . . . Pompous Garden, Porno Garden, Protein Garden.' It reads like a promptsheet for designers, a call for conscious artistry, encouraging the artifice which gardens have always thrived upon (whether in Mannerist water-features or the jewelled mechanisms of Scarpa's Brion Tomb).
Clement, on the other hand, takes a low-key approach. In contrast to the invited artists, he describes himself as un jardinier, disinterested in a signature work, who collaborates as 'a catalyst' with nature, to rather imprecise ends. His intervention, he implies, must be something other than an eye-catching temporary installation and attuned more subtly to the existing garden.
As it happens, among the most successful contributions to 'Le Jardin 2000' is one where artifice is paramount - Zaha Hadid's Meshworks. With multiple lengths of taut red cord, she dramatically reconfigures a square hedged 'room' as if with a huge three-dimensional drawing. The lines of cord, dynamising the space in every direction, swoop and soar, fan out and converge, criss-cross and warp; their red sings out against the complementary green. Tree trunks, statuary, even a gable-end and wall beyond the enclosing hedge, are incorporated into this tense intricate scheme.
It's an abstraction that forces the body to adapt (you can negotiate most of it with some strategic ducking); and indeed Hadid envisages this garden as a stage for performance at some point during the exhibition.
In another of these green rooms, Alfredo Pirri has created his Via d'Ombra - a raised walkway that meanders and branches through a lofty grove of bamboo. The continual small shifts of direction prolong your passage in this shaded realm, and sporadic stele-like features, hung with glazed panels, further invite you to pause.This coherent small world is satisfyingly distinct from anywhere else in the villa's grounds.
Bertrand Lavier turns his hedged square into a one-hole golf course, complete with bunker and manicured green. Two contrary landscape modes, each with a period of dominance in shaping the natural world, are brought into conjunction; it is amusing, though no more than a one-liner. A labyrinth of rosemary bushes sounds appealing; unfortunately, Luigi Ontani also includes his own polychrome version of the herms which populate the Medici gardens, along with two giant eye-pierced 'eggs'- all too kitsch for comfort.
Much more alluring is the seemingly artless Il Basilico of Jakob Gautel: towards one end of his green room, fringed by broken columns and chunks of masonry, is a dense patch of pungent basil, simulating wildness. It looks like a scene devoid of human agency; something discovered, not contrived; and it makes you contemplate more closely the square enclosures elsewhere at the Medici which have not been annexed by artists but left to their own devices.
The most obviously architectural insertion, enclosing the pool and obelisk at the centre of the piazzale in front of the villa, is a hollow doublecube pavilion by Daniel Buren. Covered inside and out with mirror-glass, it is brash, glitzy and alien in these surroundings - and such fractured reflections have been seen too many times before. The architectural pleasures which 'Le Jardin 2000' offers are irrespective of the merits of any new exhibits: the chance to visit Ferdinando de Medici's studiolo, decorated with beautiful bird-thronged frescoes, and to see the highvaulted stuccoed cistern beneath the villa itself.
To the south of the piazzale, off a broad terrace reached by a lateral stair, is the entrance to the Bosco, accentuated at present with a translucent tubular tunnel by Italian architect Stalker. There could be more poetic ways of treating this transition. At the far end of the woods, in the tiny hexagonal tempietto on top of the belvedere, comes one of the most economical interventions in the whole exhibition - Cerith Wyn Evans'quotation marks in neon, placed on either side of the opening that looks back towards the villa's twin towers across the intervening trees.
In saying that this framed scene is a citation, it evokes the precedents by which we perceive (and perpetuate) landscape. One could think of the Romantic sensibility that sought to make the world into a Claude painting; or of Ian Hamilton Finlay's inscriptions in his Stonypath garden ('See Poussin, Hear Lorrain'); or simply of a postcard cliche.
The Bosco is the site for Gilles Clement's contribution, determined in collaboration with Nicolas Gilsoul - and certainly unobtrusive at present.
'With the coming of summer and the fading of the acanthus, remove the dry leaves, one plant at a time. Then distribute the silver mulch of the dead leaves. Plant about 10,000 gaura lindheimeri, verbena bonariensis, nicotiana sylvestris in a random pattern.' So far 3000 gaura have been planted, and their first white flowers are just appearing.
'A minor act of gardening, nothing more, ' says Clement; but though proceeding by stealth in contrast to some of the artist exhibitors, he seems set to make a real difference to the gardens' long-term look.
One further feature in the Bosco calls for comment: the 'folly' designed by Gruppo A12 (with input from, among others, Cedric Price), which is not a folly in eccentricity of form - more a simple garden shed, glazed and with a wooden floor, in the 'primitive hut' tradition.But it is far from primitive in its contents (eg Internet access) which, drawing especially on dossiers compiled by Barbara Nemitz, form a comprehensive archive of contemporary gardens and give a broader context to the exhibition.
There is a sonic element here - Natasha SadrHaghighian's 24-hour soundtrack recorded in the villa's grounds, playing out-of-synch with real time - while sunlight filters through the trees outside. It's the perfect place to take stock of 'Le Jardin 2000', which, whatever else it does, suggests that Hadid's overt artifice and Clement's discretion have equal validity in garden design.