Musing about a mossy issue

87553271Moss is somewhat like curly hair. Those with lots of curls envy those with straight hair, and those with straight hair want the curls.

Some gardeners strive and strive to get moss to grow in their yards, between bricks and patio pavers. They want their pots to show the aged moss effects. Some even will develop moss gardens in all sorts of containers, ­creating miniature mountains of moss.

They will create concoctions of butter­milk and water or yogurt and water, spraying or misting the moss daily to get it to grow and keep it green and lush, often smelling up the landscape with fermented lactose products.

And there are those where the moss seems to be doing well on its own, thank you very much, and thumbs its collective noses at our attempts to control it, sometimes thriving even more with every attempt to drive it from our landscape.


Like anything, it helps to know the plant to try to duplicate its ideal habitat if you are trying to get it to multiply, or change the environment to make sure it’s breathed its last bit of carbon dioxide.

In the grand scheme of plants, moss is a Bryophyte. It’s a green plant, manufacturing food from carbon dioxide and water. However, it doesn’t produce flowers like most plants, ­producing spores instead.

Nor does it have a vascular system, which would be like taking all your blood vessels out of your body and having the blood just flow here and there in your body. Since the water and food mix, and there’s none of those botany terms such as xylem and phloem, moss doesn’t have the ability to create stems. So all you have are leaves or leaf-like structures packed on top of each other.

The lack of stems is what separates fern from mosses.

Most Midwest mosses typically go to town where the area is shady, moist, humid, moist, compacted soil, shady again, moist again, high pH or low pH, and moist for the final time. In other words, lots of moisture and shady conditions are perfect for moss.

Moss also like a highly organic material to develop on, such as a ­forest floor, heavy thatch in the soil, or a shake shingle roof.

Which when you think about it, is why you see moss on the north side of objects, or in the middle of a forest.

So, if you WANT moss, keep the area shaded and moist. The buttermilk or yogurt concoctions add the necessary organic matter, but it really does smell. Some people will actually take some moss and throw it in a blender with the buttermilk and then spray it on pots, troughs, bark, etc. to get the moss to grow. Make sure to wash the blender thoroughly afterwards, though moss isn’t toxic.

For those wanting to rid their yards of moss, you need to open up the area to sunlight. Of course, this may mean thinning trees to let more sunlight in, thereby increasing your air ­conditioning bill. It may involve removing trees.

You need the soil to drain quickly. If you have a clay soil, your best bet is to move to Arizona where the soil drains quickly and moss isn’t common except in the higher elevations.

Aerating the soil this fall, which involves punching holes and ­pulling out plugs of soil, is one way to ­encourage drainage. You may have to do it for several years in the fall. Aerating also encourages grass to grow, which can eventually choke out the moss.

Don’t water the mossy areas, or if you do because there’s grass there, water deeply so the grass roots will find the moisture but the shallow moss roots won’t.

Check the soil’s pH and if it’s way above 8.0 or below 5.5, you’ll want to try to change it.

David Robson is Extension Specialist, Pesticide Safety for the University of Illinois.
David Robson is Extension Specialist, Pesticide Safety for the University of Illinois.

If you have moss between spaces in the patio, sidewalk or driveway and you don’t want it, boiling water or ­vinegar should do the trick, though you may have smelly cooked moss around for a bit, or a pickling smell. Neither should harm deep-rooted plants.

There are some chemicals around for moss control, but unless you change the environment, it will return.