Is there a way clean up your tiles and stepping stones without damaging the enviroment? I have every year a lot of greens (how do you call this in english?) on it and I don't want to use the damaging products anymore.
I just use a little pressure nozzle (brass or plastic -- but I prefer the brass ones -- about 2 or 2 1/2 inches long, available wherever things like lawn sprinklers are sold) on the end of my garden hose. If your tiles are really bad, from years of not being cleaned, you could rent a pressure washer. You don't need to use any kind of chemicals., even vinegar. Just plain water under pressure cleans off all moss very nicely.