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Tree friendly deck cleaner

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.

Re: Tree friendly deck cleaner


Over the years I have stripped many decks, including my own, using caustic strippers. As far as plant damage, the most important thing is to make sure you wet the leaves down before, during and after the stripping. What goes into the ground does not seem to do permanent damage. Caustic strippers are always followed by a treatment with mild acidic wood bleaches, mostly containing diluted oxylic acid. The acid not only brightens the cedar back to almost like new, but neutralizes the caustic residue on the deck and environs.

Deck strippers do not cause the old stain to crinkle up like regular paint strippers, but rather to dissolve them into a slippery, soap like substance. Generally, the stripper is put on in a generous film and allowed to work for about 30 minutes. If it starts to dry out, more stripper must be applied. Scrubbing with an old fashioned scrub brush on a stick helps with the process. The residue is then blown off with your power washer. Make sure to spray your house first and constantly during the removal process to prevent the residue from marring the house finish. The deck will clean off do bare wood, but subsequent rinsing will continue to suds up. The sudsing will continue until you apply the neutralizing acid.

Make sure you wear sturdy shoes and long pants during this cleaning. The deck stripper can give you a good chemical burn if allowed to remain on the skin. Wear eye protection too. Keep clean water around to rinse your skin. A little vinegar will also help prevent burns.

The last time I cleaned my deck, my perrenials and lilac bushes were literally swimming in the residue. However, I gave them a vigorous rinse with the power washer and blew the dirty water onto the lawn. Everything survived, even though I had my doubts at the time!

Re: Tree friendly deck cleaner

Thanks so much for your help, I greatly appreciate it and will take it all into account!

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