We have a couple of wooden Pergolas. Between the uprights and shaded from the sun we have two 6' x 5' trellis panels which are covered in green Algae after the winter months.
When cleaning some nearby paving with 40% strength white vinegar the overspray cleared the Algae without any further assistance so I put some in a sprayer, lightly misted the trellis and an hour or so later the green had gone. By next day the wood generally looked cleaner.
Mask up and wear eye protection if you try it and make sure there's zero wind.
When cleaning some nearby paving with 40% strength white vinegar the overspray cleared the Algae without any further assistance so I put some in a sprayer, lightly misted the trellis and an hour or so later the green had gone. By next day the wood generally looked cleaner.
Mask up and wear eye protection if you try it and make sure there's zero wind.