Wood
Quality and price can vary greatly here. Teak and mahogany benches, for instance, can cost between $400 and $600, but last for 20 years or more, even if left untreated . A cheaper alternative: white cedar. If treated, says James, a bench made of white cedar will last almost as long as one made of more expensive woods and cost about a third as much.
Treated pine is another good option that might be within your budget.
Wooden furniture is a favorite for many gardeners because it is lightweight and can be moved around the yard easily when you need to mow or want a change. James recommends applying a protective sealant during the first year or two of use, however. Paint, stain or water sealer (like the ones used to treat decks) work well.
Wrought Iron
Iron furniture has been around for years and is another good choice for the garden or patio. Again, prices vary. James recommends purchasing products with a powdered coat finish. "The furniture will last a whole lot longer, and it won't rust," he says.
Wicker
Wicker is one of the more aesthetically pleasing (though expensive) options for outdoor furniture. But, cautions James, even if you paint it, stain it or otherwise treat it, wicker should never be left outside year-round. A new alternative is faux wicker, made of weather-resistant plastic resin. It comes in a variety of colors and looks remarkably like the real thing.
Plastic
Furniture made of plastic is generally cheap, lightweight, maintenance-free and can be left outside forever--what more could you want?
Stone
Furniture fashioned from stone provides a natural look, is surprisingly affordable and has the added benefit of being a more or less permanent fixture in your landscape (if permanence is what you're looking for).
Fabric
You may not consider a fabric hammock a true piece of garden furniture, but it does provide a great place to relax in the garden. James points out that the fabric styles are mold- and mildew-resistant and therefore last much longer than the rope ones.