You need to spray a moss and algae preventer now before the rains come. I use Safer's Alagae and Moss preventer as it won't harm the plants. Follow directions on the package for any product. To give some instant traction sprinkle a bit of kitty litter or sand on the area. Don't use salt as this will wash into the soil. I also think moss is beautiful - in the right place! Keep growing, Marianne