How do I stop the moss and black discoloration on my roof shingles?

When I lived in Portland,Oregon n had a shaker roof that wasn’t red wood we did this ! If it’s really bad Ull need it professionally power washed with strong pool chlorine ( make sure all plants soaked with water n covered with plastic as my roof cleaner doers now that I live in very wet humid Fl ). unless u own or rent a gas one n clean it urself.

TO maintain a clean roof just Run n attach several rows of copper wire across the top of ur roof n when it rains or u shoot water up on ur roof with a power washer the copper chemicals will run down n kill n keep killing mold but never killed any plants

Home improvement stores sell exterior wall cleaners for diy. They connect to a garden hose and are plant safe. No bleach! Read the labels.

There is a special spray which you can attach to your water hose to kill the moss. Some people put zinc strips just under the top row of shingles so that when it rains it runs over the zinc and down the roof and helps to keep the moss from forming. Excess moss will eventually deteriorate your roof shingles. Trim all overhanging branches from above the roof. Hire someone if you have to because it is cheaper to fix it now that replace the shingles.

I have heard that strips of zinc under the top roof shingles will keep the moss from forming. Maybe if you look this up on the web there will be more info. Apparently it works well as long as there is plenty of rainfall or you would have to hose down the roof often.

Trim/cut back the trees that are near the house/roof then have roof pressured washed. I was getting moss/mildew on my roof due to a nearby tree and I had the tree removed and solved the problem. No more dirty roof.