I sprayed it on with an ordinary two (2) gallon pump sprayer, using one gallon of mixture at a time. I followed the mixture directions exactly as stated on the gallon bottle. The weather was dry for the day and the next day. Three (3) weeks later, I checked the roof to see if any change. The bright green moss growing on the asphalt shingles had turned to a tan/brown color, but the black mildew was still the same color both on the roof and the garage cement wall's entrance. So while it is too soon to say it will work as advertised, it does show signs that the moss has stopped growing and looks like it is starting to die. From Seattle on 27 Feb 2011"..." Read more
- Seattlep in Seattle, WA