Powder coated or painted finishes are intended both to disguise and protect natural materials, but in gardens natural materials are often a popular choice, either because some finishes look modern or because their natural appearance enables the lights to blend into the environment. So how do they weather once you take them out of the box and expose them to the elements? Most materials will weather to a reasonably uniform or mottled finish, but bear in mind that pollution near roads and industry can result in drops of tainted rainwater and airborne particulates which can result in a more blotchy finish. If this happens an easy solution is usually to clean the light fitting with bathroom limescale remover to take off the surface film and let it weather again more naturally. You can accelerate weathering by watering lights which are sufficiently weatherproof with a watering can or hose (be careful with pressure hoses - you might get more than you bargained for!) but then remember that tap water contains chemicals which might affect the weathering - making your copper lights go green if your water contains an alkaline element, for example.
Aluminium is a robust material which is generally the lowest cost option for garden lighting, as well as being one of the most efficient dissipators of heat from the lamp inside. So aluminium fittings tend to enable longer lamp life, but some products in natural aluminium can weather to an unpleasant blotchy finish, so most aluminium garden lights are powder-coated in suitable colours - typically black, green or rustic brown for spike spotlights and black, rustic brown or silver-grey for wall downlights or black, rustic brown or white for wall spotlights
Copper garden lights typically weather to a mottled brown finish to blend with brickwork, bark mulch, woody planting and timber. Weathered copper spreadlights are the most popular of this type of light fitting as their weathered appearance looks much more natural in the garden than any other metal or painted finish. Copper wall spotlights such as Elipta's Compact copper downlights and copper steplights such as the SMOOTHIE are popular choices for red brick walls and timber structures for the same reason. One lady looking at copper lights at the Chelsea Flower Show was heard to say "how often would my housekeeper have to polish those?" and enquired about lacquering them to stay shiny - lacquer won't last forever, but do you really want shiny copper lights in your garden? Copper spotlights are likewise popular for their discreet, weathered appearance in gravel or bark mulch. Weathering will typically take 4- 8 weeks depending on the weather. Copper led lights can also weather into an unobtrusive finish when installed in timber structures, particularly hardwood decking
Brass garden lighting typically weathers to an ochre colour which goes well with decking and stone, particularly if it has a textured, sandblasted finish which gives them an attractive semi-matt appearance to begin with. Polished brass tends to weather less predictably to a darker finish and is less widely used in garden lighting. Useful features of brass garden lights are that they are heavy enough not to be disturbed easily and are as tough as old boots - corrosion proof even on the sea shore as well as proof against impact. Surface mounted steplights featuring a sandblasted finish to look good on sandstone and buff brick have weathered nicely in trials on timber planters and stone walls. Brass is one of the best materials for underwater lighting, being mechanically robust and resistant to all chemicals as well as heavy enough not to be disturbed easily by fish or water currents. Brass can also weather into an unobtrusive finish when installed in timber structures
Stainless steel is often the finish of choice for modern gardens, particularly for recessed lights in decking, such as the Navigator range, and wall lights such as Elipta's Compact wall spotlight range. The highest grade 316 stainless steel is used for most fittings, but stainless doesn't mean self-cleaning - you will need to clean them periodically to remove typical exterior tarnish left by hard water spray, airborne pollution, birds, insects and blown leaf litter. Marine grade 316 is essential for seaside locations, but some brown-spotting can still occur and there are proprietory stainless steel cleaners to deal with such transient discolouration.
There are a number of ranges of wooden lights on the market, usually a wooden sleeve encasing a weatherproof lamp housing. Many are cheap imports made of cheap pine which discolours and cracks sooner rather than later. Even lights made from good quality teak will need the same annual maintenance as teak garden furniture - installation instructions will say they need an annual treatment with oil to keep them looking good, but that is what most clients who buy this type of light will accept as part of buying a natural product. Some clients stain their wooden bollards with wood stain once the original appearance has weathered, but if you can be bothered to get a tin of wood stain, why not use natural oil instead?
There are also a number of ranges of stone lights on the market, usually a sleeve encasing a weatherproof lamp housing. Many are cheap imports made of "reconstituted stone" - concrete to you and me - which looks cheap and plastic (sometimes real plastic!). Good stone lights are few and far between and they are certainly not cheap.
Copyright 2014; Information based on products supplied by Lighting for Gardens Limited and is advisory only. The company accepts no responsibility for incorrect use or application of information given. Light fittings can become hot in use; exercise appropriate precautions. Exterior electrical installations should be undertaken by a qualified electrician.