TOOLSHED

Why is the decorative potential of outdoor illumination so rarely exploited? Light is a fundamental, with infinite and subtle variability. On the purely practical side, garden lighting has the obvious benefit of extending the hours we can enjoy the garden. This is especially welcome during summer when dinner al fresco is a realistic proposition, but at other times of year it at least allows us to see the garden from indoors. The use of bright, overhead lights around the home to deter intruders is also useful. And there's the safety aspect: lights can improve access and safety on steps, paths and driveways.

As so often, it is when we move from the utilitarian to the aesthetic that things become really exciting - and the scope for dramatic garden effects using artificial lighting is huge. Back lighting with a wide beam can throw plants and structures into relief and accentuate their form; uplighting adds new perspective to planting; directional spotlights can be employed to pick out particular features . One of the most atmospheric techniques is called moonlighting - a soft light is placed at high level to cast a gentle, shadowy illumination. But in the excitement of electric possibilities, don't forget the charm of flares and candles - what could be more romantic?

A combination of subtlety and simplicity is required if the results are not to be impossibly garish. In general, a number of smaller, lower voltage lights produce better results than a single very bright one, which has the unfortunate tendency of making a garden look like a gulag.

Light type - whether spot, recessed, post and so on - should largely be determined by location and function. When choosing styles it is usually best to go for something fairly neutral that will blend in. There is a clear choice between mains and low-voltage lighting. Low-voltage lights are smaller and easier to conceal, as well as generally being simpler to install. As their cables do not necessarily have to be permanently fixed, they are transportable and many are fitted with ground spikes and clamps for this purpose. Their 12V supply, stepped down via a transformer from the 240V of the mains, is also inherently safer, and no harm will ensue even if a cable is inadvertently cut. On the downside, they have lower light output, a restricted cable length and with the addition of a transformer, are expensive to buy. Mains lighting, however, will almost certainly require the services of a professional electrician and involve the expense and disruption of laying proper electric cables. Do try and think of your lighting requirements before, and not after, paths and paving are laid or new borders planted up.

Whatever you choose, installing garden lighting is never likely to appeal to very budget-conscious gardeners but the addition of even a single, well-placed light can have real impact.

Tom Barber

In garden centres you are most likely to find the following makes: Garden (01462 475015 for stockists) and Hozelock (01844 291881 for stockists). Both do a range of easily installed low-voltage lights available as complete kits. For teak light fittings try Indian Ocean Trading Company (0181-675 4808). For a wide range of fittings and specialist advice try: John Cullen Lighting (0171-371 5400); Garden and Security Lighting (0171-231 8282); Outdoor Lighting Supplies (0181-974 2211).

Tom Barber presents Channel 4's Garden Party on Fridays