IN A HUGE, darkened hall, part of a disused Hamburg factory, a drop of water hits the flooded floor. The splash is picked up by a microphone, and the amplified sound fills the air. At the same time, a giant projected image of a droplet and the ripples it creates appears on one of the walls. Strangely, this wall and the two next to it bear a dense covering of grass. Seconds later, the projector dims and the lights are turned up to reveal a pattern of yellow and green grass that forms a negative of the projected image that it has just replaced. Then the room lights dim, another drop forms, and the process begins again.
This is Reversing Fields, the latest work by the British artists Heather Ackroyd and Daniel Harvey. The exhibit will form part of the Hammoniale Women鈥檚 Festival 95, an international festival of modern artforms which opened in Hamburg this week. The two artists have spent the past three weeks converting the hall, using grass growing techniques they have developed especially for exhibits such as this.
Ackroyd and Harvey began collaborating in 1991, having previously spent ten years working independently with living materials such as grass and fungi. 鈥淲e have different ways of growing grass: up walls or onto a fabric, for example,鈥� says Harvey. Later that year, they stumbled upon the idea of using a grassy surface to record an image, when a ladder propped against a grass-covered wall left an imprint of its shape. Starved of light, the grass behind the ladder had turned yellow.
Advertisement
That November, they used the idea to create yellow and green stripes on a grass coat that was exhibited at an anti-fur fashion show in London. The coat was made of hessian, which was moistened and sown with grass seed. As the seeds germinated and the grass seedlings grew they were kept in place by their roots which became entangled with the fabric. The stripes were produced by covering the coat with a stencil. 鈥淭he grass grew thicker and healthier where the light fell,鈥� says Harvey. 鈥淎nd the pile of the grass gave it a three-dimensional quality,鈥� echoes Ackroyd. But the coat was uncomfortably heavy to wear and within a few weeks the grass died. The dried remains now hang in the corner of their studio in Dorking, Surrey.
Now Ackroyd and Harvey present two or three grass exhibits each year. The process is roughly the same each time, but the installation they are creating for the Hamburg show is more ambitious than most. The three vast walls in the old factory present an area of 350 square metres which will be covered with 750 kilograms of clay and 300 kilograms of grass seed. Three weeks ago, they began stripping the walls down to the bare plasterwork, then smeared them with a layer of soft, moist clay a few millimetres thick. Getting the moisture content right is crucial. If the clay is too wet, it will slide off the plaster. But last year, at an exhibition in Perth, Australia, they had the opposite problem. The clay became too dry and starting peeling away. 鈥淚t was minutes before we opened when I noticed it,鈥� says Ackroyd, who swiftly repaired the damage by wetting the clay and sticking it back to the wall.
Gardeners making a conventional lawn usually sow enough grass seed for one seedling to develop in each square centimetre of soil. Growth is always patchy initially, but when the grass is cut, the roots spread out beneath the surface and sprout again nearby to fill in the gaps. But mowing a vertical lawn is impractical, and Ackroyd and Harvey have to create their grassy surfaces quickly. So they guarantee a thick, even growth by planting roughly 10 seeds on every square centimetre of clay. The seeds must be pressed onto the clay by hand to prevent them falling away. The finished surface resembles a sesame seed cake.
After the seed has been sown, the walls have to be sprayed with a hosepipe three or four times a day to make sure that the clay doesn鈥檛 dry out and crack. When the grass has germinated, after five or six days, its roots help to hold the moisture in the clay and from then on it only needs watering once a day.
The sowing of the seed is carefully timed for germination to begin roughly a week before the exhibition opens. From the time the seeds germinate, the artists project a black and white image onto the grassed area. For the Hamburg exhibit, it is a picture of a water droplet splashing into a pool and the concentric ripples it creates. Grass in well-lit areas grows thick and healthy, while grass deprived of light becomes yellow and spindly. The resulting colours are surprisingly varied: dark greens appear almost black alongside the acidic yellows of the etiolated grass, with a variety of midgreens in between. The result is a negative image of the picture covering 144 square metres of one of the walls.
During the festival, the hall will be lit alternately by ambient lights, revealing the negative image, and by a projector showing the positive image in its place. The switch between the two takes about ten seconds. Its effect is 鈥渁lmost like an after-image retained on the retina,鈥� says Harvey. The projector being used in Hamburg was originally designed to project large images onto sets at rock concerts. It has had to be specially adapted so that it does not overheat as it is continually switched on and off.
Under the ambient lighting, the etiolated grass starts to grow more healthily, which causes the image to deteriorate. So every evening that the exhibition is on, the projector will be switched on for a couple of hours to regenerate the negative image. The periods of exposure to light create coloured bands on the grass as it grows, just as sun-bleached hair develops dark roots. The effect does not seem to bother Ackroyd and Harvey, who say they are 鈥渇ascinated with the cycle of growth and decay鈥�.
The choice of grass seed is also important, according to Ackroyd and Harvey, who have been advised and sponsored in the past by Johnson鈥檚 Seeds of Boston in Lincolnshire. They use an ordinary garden mixture of rye, fescue and bent grasses. 鈥淚f you grow a single type of seed then you are open to disease,鈥� Ackroyd points out. The mixture of properties of the different varieties in the garden mixture has other advantages, too. For instance, the rye-grass germinates in three to five days, but by the time it is 15 days old it is so long that it tends to droop. The fescue, on the other hand, is slower to germinate and has a rigid, circular stem, which helps to support the ryegrass. The slow-growing bent grass fills any gaps in the cover and ensures that the lawn remains lush throughout the exhibition.
Initially, the grass seedlings take their cue from gravity and grow upwards. But within a few days the grass begins to orient itself towards the light. This process makes for a combed look, with the etiolated shoots pointing towards the illuminated areas. 鈥淭his enhances the effect of the pile of the grass,鈥� says Harvey. 鈥淲e did one piece by projecting pinpoints of light onto a grass canvas,鈥� he adds. The well-lit areas became dark green, with the surrounding yellow grass pointing radially towards each point of light.
Eventually the lush, dense growth of the grass is its downfall. 鈥淎fter 24 to 25 days, the grass starts to get mouldy,鈥� says Ackroyd. The grass grows so densely that air cannot circulate and water becomes trapped. Within a month of the grass being sown, the clay base of the Hamburg exhibit will be stripped away like wallpaper, leaving the empty factory鈥檚 walls bare again.