What Is a Good Time to Kill Moss in Your Yard?

Moss

• Moss is an opportunistic yard problem. It usually shows up on bare or sparse areas of your lawn, moving in where there isn’t enough grass to prevent it. It comes in a variety of colors, from white to deep green, and can be an eyesore. If your lawn isn’t healthy, it could slowly encroach on the rest of your yard, spreading to replace grass as it dies. It is most commonly a problem in shady areas of lawn that don’t drain well.

Killers

• Most fungicides aren’t effective against moss growing in your yard. You can use chemicals containing iron sulfate to kill the moss you see, but that won’t protect your lawn from the moss coming back. You are better off using cultural changes to kill and get rid of it. Start by changing how you water your lawn: Do it deeply and infrequently, rather than lightly and often. Next, trim back any overhanging tree branches or shrubs in the mossy area. They block sunlight from reaching the ground, and the shade encourages moss growth.

Timing

• It is best to kill moss in your yard as soon as you see it show up, rather than giving it a chance to establish itself and spread. If possible, work on a sunny day. Sunlight helps prevent moss growth, and removing it in the sunshine will reduce the chances that any remnants will reestablish themselves. Try to work with dry ground both for ease of cleanup and because it is less hospitable to moss.

Considerations

• If you have repeated issues with moss in one area of your yard, changing the time when you kill it probably won’t help. The problem is with the location itself. Consider replacing the grass in that spot with something moss can’t overwhelm, such as a tree, bush or even an ornamental landscaped area framed with mulch or gravel. These options stand up to areas of poor drainage better than grass.