Q: There is moss growing between some of the concrete pavers of my sidewalk. Is there a reason to remove it? Will it spread into the lawn?
A: We get two common questions on this topic: “How do I get rid of moss?” And, “How can I encourage moss to grow?”
Whether to let the moss grow between pavers is really a matter of what you like. Some people think it looks untidy. Other people love the soft, natural look of moss between flagstones or pavers.
Moss isn’t likely to spread into your lawn unless your grass is unhealthy. Moss doesn’t kill grass; it just takes over where it’s too damp and shady for grass to thrive. If you want to get moss out of a lawn, you can rake it up, but then you’ll need to do something to make that area drain better and receive more sunlight if you want to grow turf grass there.
Some people deliberately grow moss as a groundcover where it’s too damp for turf grass. It can be quite attractive. It’s also low-maintenance, and it can be a good choice from an ecological standpoint. It doesn’t require mowing or pesticides, and it provides habitat for beneficial insects.
Another advantage of letting the moss go in your walkway is that then you don’t have to do battle with it! Removing moss can be tedious, and it’ll come back as long as growing conditions favor moss. If you really want to be rid of it, you can dig it out, or you can try one of the chemicals labeled for treating moss. Be aware that many of them are toxic to aquatic creatures.
If you decide you want to go in the other direction, and grow moss between ALL of your pavers, you can get it to spread as long as growing conditions are right. Moss likes damp, shade, and acidic soil. You can transplant moss like sod. You can also make a thick slurry of moss and water in a blender and apply that to the area where you want more moss. Keep your new moss moist until it’s established.
Written by U of M Extension Master Gardeners in St. Louis County. Send your questions to firstname.lastname@example.org.