At shows I'm most frequently asked if there is maintenance required on my furniture. The two major benefits of applying a finish on your furniture are color retention and conditioning the wood, helping it to last many years. If left alone the wood will weather to a silvery grey.
The amount of maintenance depends on how much time your furniture spends in sunlight during the day. If your furniture is going to be placed around your pool in direct sunlight most of the day, I suggest that you apply a coat of finish every year. If your furniture is going to be on the north side of your house under a patio cover, it may be several years before maintenance is required.
I use a product called Superdeck Transparent Stain (natural color #1910) when asked to finish any order prior to deliver. My motto is take care of your furniture and it will take care of you. I'm always available by phone to discuss any finishing question which may occur.