Use the deck stain or deck stain/sealer combo with a low-nap roller with a long cope with or even a specialty pad created for spreading stain on deck boards that have gaps in between them. To learn if a deck is ready to acknowledge a stain, consider the h2o test. http://bookmarkswing.com/story9412079/a-secret-weapon-for-how-much-to-wash-and-stain-a-deck-with-old-stainb