Moss is Not a Good Compass

I was asked the other day how to get rid of moss in the lawn. My first thought was why in the world would one want to get rid of moss? It’s colorful; in fact, it comes is several shades of green and even some with rust and silvery tints.  You don’t have to mow it. It requires no maintenance at all, actually. If it appears in your yard then it’s perfectly happy to be there.

However, it happens that the unwanted moss had appeared in the corner of a beautiful flower garden, in the space having been occupied heretofore by zinnias every summer. Therefore, it was not wanted in the spot it had chosen. Before I thought, I said, “Dig it up. Dig deep and amend the soil before planting anything else there.” Instinct jumped right out there before the brain engaged.

The experts advise to kill the moss, not just dig it up. I suppose this is because moss does not push other plants out to establish a home for itself, it just takes advantage of unoccupied real estate. That dirt, however, has some issues of its own, such as poor drainage, lack of sunlight, compaction, or low pH. Moss will move right into this poor neighborhood and love the shade and moisture and high acidity. Grass loves none of those things.

The first step is to apply chemicals to kill the moss, specifically ferrous sulfate or ferrous ammonium sulfate. Once the moss is dead, rake it away and plant grass seed, keeping the area moist until the grass takes hold. Of course, that moisture is what the moss liked in the first place.                 Too much shade? Cut a bunch of tree limbs off and let the sun shine in.

Compacted soil? Moss loves to have a solid surface to grow on. Soil full of thick intertwined roots from surrounding plants provides a perfect base on which moss can thrive. How much digging do you really want to do?

Moving from unwanted moss to moss that we do want we find peat moss, which we repeatedly use as a soil amendment. Peat moss is the dead fibrous material that forms when moss and other living material dies and decomposes in peat bogs. Peat moss has an acid pH so plants like camellias and azaleas love having it around. In addition, peat moss takes forever and a millennium to break down, so one application in your lifetime is probably enough. The problem with peat moss now is that the environmentalists have gotten involved and only .02 percent of the bogs can be mined. You see, massive amounts of carbon are released into the atmosphere when you dig up peat moss, and it continues to be released long after the mining is over.

On the other hand, peat moss holds several time its weight in moisture – good in potting soil – and hangs on to lots of nutrients so they don’t wash out when you water your plants. If you have trouble deciding whether the benefits of peat moss outweigh the environmental concerns, just use compost instead.

The real cautionary tale with moss, however, is this: it has long been said that moss only grows on the north side of trees. That’s in the northern hemisphere; in the southern hemisphere moss grows on the south side of trees. Added to that, some moss will only grow on certain types of trees. So, if you’re lost in the woods, don’t depend on the moss to guide you home.