A little moss growing in the right places (between walkway stones, for example) can be a pretty outdoor accessory—but moss climbing a brick wall isn’t a look most homeowners want. Remove it with a simple water-based cleaning method and some good old-fashioned elbow grease. You’ll need a bucket, a long-handled scrub brush, and bleach, and you should always wear gloves and eye protection for safety. Wet down the wall before you start scrubbing to keep overly dry bricks from sucking in the bleach solution.
Mix two cups laundry bleach per gallon of water, then dip the brush into this mixture and start scrubbing the wall from the top down. Proceed slowly and methodically—you don’t want to miss any areas. It may take a couple of scrubbing passes to remove all of the green. When you’re done, rinse the wall thoroughly with a hose. (You also can use a TSP/water combination, but it can be hard on surrounding plants, so work sparingly and minimize absorption by soaking the ground nearby before beginning. It also can fade adjoining paint, so tape accordingly.)