How to Kill Moss With Bleach
Exposure to sunlight is the best way to kill moss. Moss needs shady, moist conditions to survive and it quickly dies when the sun's rays shine on it. However, bleach is a close second. It will effectively kill moss within a matter of hours. And, it can help keep moss from growing back. Moss can't live on inorganic surfaces alone. It needs a thin layer of dirt or other organic material to gain a foothold, and a periodic bleach scrubbing will quickly get rid of that.
Mix a 30% household bleach and water solution into a large bucket or spray bottle (depending on how large the mossy area is).
Pour or spray the bleach solution onto the mossy area.
Leave the bleach solution on the moss for 1 hour.
Hose the bleach solution off.
Scrub the area with a scrub brush and the bleach solution. This will effectively remove any remaining dead moss and clean off any of the organic matter that it needs to grow. Periodically scrub the area with the 20% bleach solution even if you don't see any moss growing to make sure that it doesn't come back.
Kill Moss With Bleach
Moss is a collection of a bunch of smaller plants that have grown together. They thrive in shady locations. Moss may grow on parts of your roof, sidewalks or driveway that aren't directly exposed to the sun. Pour one bottle of bleach into a large bucket. This gives you a 50/50 solution. Carefully pour some of it into a watering can, which is much easier to use when you are ready to apply the bleach/water solution to the moss. Use the watering can to drench the moss with the bleach/water solution. Start at the top and work your way down. Once the moss is soaked, it should begin working in as little as four hours. You will notice the moss turning a yellow color.