North or shady side exterior?

If its MOLD bleach will kill,remove it but protect your plants.

Moss might need a copper based compound to kill/remove it, I can't think of the chemical name or product name, but its similar to what is used to clean north side shaded roof shingles, but made for verticle surfaces, however not sure if its okay for concrete. Sorry I prolly shouldn't have posted without being able to remember what that stuff is called. Not sure if TSP would be helpful either.