Just about midsummer, we start to see moss on lawns and the plaintive cry goes up, “How do we stop it?” How do we create that moss free lawn?
The first thing to understand is that moss is not going to survive in a healthy lawn. The existence of moss is a symptom the lawn is not in good shape.
Here are the simple steps.
Thicken up the turf.
Thin grass allows moss to thrive. Apply two pounds of grass seed per thousand square feet of lawn every fall to thicken up the lawn and mow existing turf at the highest mower setting.
Feed The Existing Lawn
Moss also tends to invade lawns with low fertility problems so the second thing to do is feed your existing lawn.
Ensure it is getting a full two pounds of Nitrogen per thousand square feet and check how to do this on websites or at your favourite garden centre.
Feeding lawns at rates higher than two pounds per square foot tends to produce lush grass that overgrows and is more attractive to insects.
Overfeeding is also a major cause of thatch (note that thatch is another symptom of poor lawn management).
Even though we live on an island with a great deal of water surrounding us, our lawns are on thin soil so they tend to dry out quickly. This one fact pretty much stops moss in its tracks. I’m working to thicken up the lawn (add grass seed every year) and little by little, the lawn is starting to resemble a “lawn” instead of a mowed hay field. It’s not as high on my priority list as it would be in a suburban setting (most neighbors have the same kind of lawn)
The only place we developed some moss was in the backyard in the deep shade where I kept that area lush and green in an attempt to kill off some goutweed with regular shots of organic herbicide. The combination of shade, excessive moisture and regular spraying with a soap herbicide killed off any competing grass allowing some moss to begin establishing itself. The grass is slowly coming back in that area now the excessive moisture and organic sprays have stopped. (Plus I’m sowing seed it back there every fall as well.)
This is all by way of saying that moss usually requires either a severe dose of one of the factors above or medium doses of several of the factors.
Moss is also created by excessive shade.
If shade is the problem, either cut down the trees or substitute ground covers (like moss!) for the grass.
Poor Soil Drainage
Poor soil drainage is another culprit and this excessive water creates conditions beloved of moss. The solution to this is fairly obvious “improve the drainage.
You may need a landscaper to calculate and do this work.
Finally, poor compacted soils support moss rather than grass plants.
Aeration with a coring machine will help solve this problem as will keeping the lawn roller off the turf.
Short Term Solution That’s Often Recommended.
The short term solution is to apply iron-sulfate to the lawn at rates recommended on the labels. This will “burn” away the moss but the moss will return unless the underlying conditions are remedied.
A healthy lawn will not support moss.
I note if you’re trying to eliminate moss on driveways or other hard surfaces, the best solution for this is an organic soap spray much like the organic herbicides.
And yes, this kind of product works on lawns as a short term solution although it’s not great for grass either and the odds are you’ll do some damage to the grass as well as the moss.:-)
You may want to check out the other posts on sustainable green lawns here.