The most commonly sold types of patio sets are plastic, wood, teak, aluminum, wicker, and wrought iron.
Plastic garden furniture is naturally waterproof, so you can leave it out year-round. However, rain water will collect at the back of chairs and in nooks and crannies. As such, a surprising amount of dirt can form.
Wooden garden furniture can suffer through exposure to the elements and therefore needs to be periodically treated, for example with varnish. Teak is a commonly used material for outdoor furniture. It naturally contains silica, which makes it resistant to fungal decay, many of the effects of water (such as rot, swelling and warping), as well as chemicals. It is also resistant to fire, acid and alkalis, and there are certain oils specifically for the treatment of teak to help it resist weather and the adverse effects of being outside.
Aluminum garden furniture is robust and long-lasting. Despite that, agents such as suntan lotions, perspiration and car exhaust can eat away at the powder coating that protects it, although aluminum does not rust. If the protective coating is compromised it will corrode and cannot usually be salvaged.
Wicker outdoor living furniture is made from two types of material. Originally made from the stems of any one of 600 species of palms found in tropical regions all over the world, most modern rattan is made from synthetic resin, increasing the life expectancy and reducing manufacturing costs. The palm stems are tightly woven into interlocking panels, and formed into the desired structure.