Garden lighting is practical, attractive and not expensive to run, two units of electricity will light the average garden from dusk to midnight. The lighting of the walls, patios and possible danger points such as steps helps prevent accident and discourages intruders. Effective outside lighting also lengthens the time you can enjoy the garden and can reveal an unexpected attraction in familiar surroundings. This can be achieved by using fittings attached to the outside of the house or with the more mobile low-voltage lighting set. But whichever you use, it must be safe.

There are complications in using mains electricity outdoors. Many lighting fittings can be fixed to the bricks to the house wiring, but garden spotlights, pool lights and lights in herbaceous borders will need an outdoor connection. Weatherproof 13amp sockets mounted on the outside wall of the house are an inexpensive way of providing temporary lighting for the patio, but will not have the same atmospheric effect as lighting sited away from the house.

Spotlights are the most effective way of lighting a garden. Mains voltage 100 and 150 watt spotlamps screw into waterproof holders and are tough enough to withstand most outdoor conditions, the holders can be supplied with an earth spike or a mounting bracket. Spotlights can also be mounted on trees or walls to light a path or section of the garden. When lighting trees, the spotlights should be placed at ground level or low down on the trunk and directed so their light goes up into the branches.

There are several low voltage lighting sets available. These can be safely installed even at ground level, where children are likely to touch them. They operate at 12 volts through a portable mains transformer (the output of the transformer is described in volt-amps rather than watts); you simply plug the transformer into any convenient socket outlet and trail the cable down the garden, connecting in spotlamps at any point in the length of the cable. The lamps are easily attached and can be pushed into the earth on spikes or fixed to trees.

Colour is important when lighting outdoors and most spotlamps are sold with colour filters. The thing to remember when lighting a garden is to concentrate on what is being lit and not on the lights themselves. White is most effective since it brings out colour, red turns foliage brown, while yellow turns it grey. Green highlights grass and foliage, while blue has a mysterious quality especially on birch trees, it also attract insects, so place it away from a terrace or patio. Lights should be hidden from view or placed behind large plants, where concealment is difficult, you should mount them above the normal lines of vision.

Concentrate on trees and larger shrubs. Trees such as elm, which have a high canopy, should be lit from below so the spotlight shines upwards into the leaves. Silver birches should be lit so the beam just touches the main limbs and conifers should catch the light along the edges of their branches. One or two spotlights placed in herbaceous borders can give a dramatic effect, casting a warm glow over the flowers.

When experimenting, choose a dry night and use an ordinary 150 watt lamp in a simple bowl reflector. Seen from a distance, this will give you an idea of the effect you will get when you eventually install the proper equipment.