Green Scene

Using Moss to Create a Dramatic Garden

By Joel M. Lerner
Saturday, March 21, 2009

Perhaps you think moss grows like a weed because you see it everywhere -- on patios, garden furniture, lawns, the side of your house, on trees and in poor soil. It does, but only when it's happy.

When you do have ideal conditions, though, you can encourage it and create a moss garden to dramatic design effect.

These minute plants, which have a velvety look and feel, grow into thick coverings by catching dust and using their own decaying debris for a growth medium. During the prehistoric age, these carpets were the basis for all topsoil. As moss grew thicker, the bottoms of these thick masses formed rich compost, and in this soft, moist, rich environment ferns had their beginnings.

If moss is already doing well on your property, you will have to do little to make it the dominant ground cover. If you are going to experiment with mosses, it's best to stick with those that are in your back yard or from your part of the country.

One of the best authoritative texts on moss culture, history and identification is "Moss Gardening," by George Schenk. He says there are 1,200 species of moss native to North America and about 15,000 varieties worldwide.

"Gathering Moss: A Natural and Cultural History of Mosses," by Robin Wall Kimmerer, is a book that offers a mix of scientific information and personal essays.

The perfect environment for moss can run the gamut from sun to shade and acidic to alkaline, depending on the species. For many mosses in this region, shade and acidic conditions are helpful, and moisture is key to success.

A moss plant doesn't have a root system; it has a rhizoid that anchors the plant. It has no hollow tube or stalk; moisture climbs the stem through osmosis from one cell to another. It spreads through spores and by growing new stems and colonizing a patch of land, rock, brick or other material where it can thrive. A single colony that is centuries old can cover an entire property.

If the moss is doing better than your lawn, acidify with aluminum sulfate to rid the area of grass and weeds. Be very cautious when using aluminum sulfate, as it is a very acidic material that can burn moss if too much is used. Follow directions exactly.

Other methods of acidifying the soil to make it more hospitable for moss are wettable sulphur and iron sulfate. Wettable sulphur has a negative side. It kills good and bad funguses in the soil. So iron sulfate may be the safest method, used according to labeled instructions. It might take a little longer, and it will stain concrete or flagstone.

Instead of raking moss up and discarding it, try cutting pieces and planting them in other areas where they might look good. Sprinkle with water to help the plant establish. As with any ground cover, one of the greatest challenges to establishing moss is weeds. In the case of moss, getting rid of them is a painstaking process. Count on plucking seedlings from the moss on a regular basis to maintain a rich carpet-like appearance.

My experience at moss gardening began when I collected varieties growing in New Jersey in sandy soil and pastures fertilized with manure that supported mats of mosses that were two to three inches thick. There were red, yellow, tan and deep green. Some were shaggy looking, others were smooth with a sheared look. At the time, I didn't know the varieties because I was 8 years old.

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