Tropics on the agenda

Boardrooms are blooming with cacti, yuccas and palms. Michael Leapman reports on the greening of the workplace

The plant doctor was puzzled. Summoned by a large corporation to look at some ailing kentia palms in its offices, he found them seriously afflicted with wind-burn. How could that possibly happen in this modern, climate-controlled building? The st aff looked sheepish, but feigned ignorance. Only when the plantsman was invited to the canteen for coffee did he twig. On the wall was a photograph of the company's float in a recent carnival procession. It had a Caribbean theme - and what better way to decorate it than with the palms from the office?

"They came clean then," said Paul Sturgess, head of quality control for Rentokil, a leading supplier of plants for offices. "But it does show you that these plants have a lot to put up with. Even the replica [artificial] ones that we supply to some customers get misused: they only have to have a Roman toga evening and everybody's got one wrapped round their head."

Plants in the workplace - and plants in the shopping mall, the bank, the hallways of flats and even railway ticket offices - have multiplied since open-plan offices and large atriums became fashionable. Like the architecture, the trend towards stuffing buildings with tropical greenery spread from the United States, where the ugly word "interiorscapes" was coined.

Until recently displays of plants in commercial premises were so rare that they were made a special feature - as in the palm courts of grand hotels. In offices, the rare touches of greenery were supplied by staff, who brought in their own little pots of cacti or spider plants and even the odd bulb to soften the workaday environment.

Now employers are themselves taking responsibility for greening the workplace. They are beginning to recognise that plants create a relaxed atmosphere that might persuade their customers and their employees to think well of them. Research at present in progress at South Bank University suggests that properly chosen plants can have tangible as well as psychological benefits, by reducing noise and keeping buildings cool.

Ten years ago, when ambitious plantings were coming into fashion, Rentokil (which most of us still think of as a pest control company) decided to enter this new market by buying a small firm in Bristol. Today it trundles tubs of giant yucca and ficus benjamina to 7,000 commercial premises all over the country, with 300 staff to look after them. "Traditionally," says Sturgess, "the industry was manned by ladies whose last child had left school and who wanted to earn pin money; so they'd find a few clients and use their domestic skills by popping the odd plant in. It was a cottage industry. Now it's done on a much more professional basis."

The annual cost for the service can be anything from £400 to £1,000, depending on scale and on whether the plants are bought or rented. The arrival of big-name companies raised the quality of the plantings. The aspidistra - a Victorian favourite that survives rough treatment and low light - may have been superseded but the designs were still in a primitive stage, according to Martin Ellis, general manager of Rentokil's tropical plants division.

"The standard method used to be to stuff as many plants as you possibly could into a container - what we'd call the jungle effect. Typically you'd put a leafy ficus benjamina and a kentia palm in a round white pot with mixed random underplanting."

What Rentokil has done is to think more constructively about how to show off the interior of a building to its best advantage. "We started to move towards stronger specimens and fewer plants," Ellis explained, "making a bigger and bolder statement. We'llhave six large plants rather than 20 small ones - things like a large yucca that are more architectural."

For reception areas or boardrooms, where a splash of colour is thought to be important, the company supplies bowls of seasonal flowering plants. These need less renewal and attention than traditional vases of flowers, and many people prefer them.

At its headquarters in East Grinstead, Sussex, Rentokil has a controlled-environment building where plants are tested, sometimes to destruction, to see how well they stand up to office conditions. Lack of light is the most serious drawback. The plants that tolerate it best are those that originate on the floor of tropical jungles, where they thrive in shade.

More thought is also being given to the containers. "We drew up a `yuk' list," Sturgess says. "White and brown were both yuk colours, so now we go for blacks, greys and royal blues. A lot depends on what you call it. Customers might say they don't like beige, but if you tell them it's ivory they'll go for it."

Every detail is thought out afresh. "It was quite traditional to leave a bare compost on top to display the cigarette ends to maximum effect. Now we put pebbles on top."

With fewer offices allowing smoking, the cigarette-butt hazard has diminished. Smoking itself does not harm plants - in fact it benefits them by keeping pests at bay - but there are other ways of ill-treating them. Spilling wine at parties may do little harm, but cleaning fluids can be fatal, especially in such venues as shopping malls, where trees are sunk into pits.

Surprisingly, vandalism and theft are not serious problems when displays are properly maintained, although in airports or railway stations delayed travellers may vent their frustration on plants. For such venues Sturgess will sometimes recommend tough plants with saw-toothed leaves - "plants that can bite back", including phoenix palms and pandanus.

A more common danger is over-eager watering. "The trick is to water infrequently and well, rather than in little dribbles every day," advises Mike Lothian, the company's tropical plants research manager. "People tend to water every time the compost feelsdry on top, and in the end that starves it of oxygen."

Getting the experts to do it for you is one way of getting good office plant displays, but in small companies there is no reason why a staff member should not take on the responsibility. The accompanying chart shows the 10 most popular office foliage plants, with cultivation hints. Just don't use them on your carnival float.