START WITH CLEANING
Working in the shade, clean furniture using an oxygen bleach to remove any loose remnants of old finishes, dirt, and mildew (unless it’s redwood; then opt for oxalic acid to help maintain its color). Mix the bleach in a garden sprayer following the manufacturer’s instructions. Spray it evenly on each piece, let it foam up for 15 to 20 minutes, then gently scrub with a soft-bristle brush and rinse with water. When dry, you may need to lightly sand the wood surface.
SEAL OUT WATER
Water is wood’s biggest enemy, and the most important line of defense is proper sealing. To that end, skip polys, varnishes, and paints, which form films that sit on the surface and eventually crack or peel, as well as some natural oils, like linseed, which can be food for mold and mildew. Instead, opt for a synthetic penetrating wood finish like Seal-Once Exotic Premium Wood Sealer ($28 per quart; seal-once.com). Apply it following the manufacturer’s instructions; expect to repeat every one to three years.
KEEP COLOR LOOKING NEW
Clear sealers don’t offer protection against the fading and graying caused by UV rays. But you can maintain or restore wood color by following up the cleaning just described with a tinted wood stain like Messmer’s UV Plus for Hardwood Decks ($46 per gallon; opwdecks.com). The pigments in a stain act as a sort of sunscr