I will be pressure washing my deck this weekend, it is cedar and needs to be stripped down to bare wood again because the old stain is chipping and uneven. Two old trees are growing very close to the sides of the deck (as well as many perennials). If I decide to use a deck cleaner, is there anything that won't kill the plants or harm the tree roots? I know I could put a tarp down but it seems like it won't catch everything. Perhaps the best answer is to not use a detergent cleaner, but I'm not sure that that will clean it off completely. Thanks so much.