Story By Susan Crawford, Photography By Dale Sievert
I’m pretty sure that in the pre-Google era most everyone who spoke of or asked about moss was trying to get rid of it. Even now googling “moss in the garden” produces five “how to kill” results before the first “how to grow.” But I recently attended a lecture at the Chicago Botanic Garden given by Dale Sievert, whose passion for and expertise about mosses made me question how anyone could contemplate mayhem against such a beautiful, ancient and eco-friendly organism. Since mosses have slowly, over the past few years, begun to colonize the damper, shadier parts of my tiny urban forest (i.e. my front yard), I was happy to be urged to encourage the process rather than fight it.
Sievert grows more than 50 species of moss in his garden in Waukesha, Wisc. and has visited gardens featuring the plant in countries all over the globe. His slide show left his listeners with mouths agape and acquisitive juices flowing. More than 300 mosses in containers. More than 600 mosses blanketing rocks. Moss growing among shade-loving perennials. Moss thriving in sunlight. The artistry involved in showcasing these tiny plants is extraordinary.
The Japanese have valued mosses for centuries for the many ways in which they can be grown and for their velvety textures that contrast so elegantly with leafy, spiky, shiny and oh, so many other characteristics of the plant world. Having started growing mosses around 2000, Sievert was inspired to visit Kyoto, Japan in 2014. His stunning photos of Kyoto and Waukesha have inspired me to go beyond letting my moss do its own thing amongst the ferns and bleeding hearts. I’d like to try covering a rock or two for a starter. If only I had a flowing stream like his, I’d let my mossy rocks sit in it as he does.
Sievert provided generous advice on how to begin a moss project.
A Bit of Basic Knowledge
All mosses are in Bryosida, a phylum originating between 400 and 500 million years ago. True mosses belong to the class Bryopsida with 660 genera and 12,000 to 15,000 species. They reproduce both sexually (from spores) and asexually (for example, from pieces that have broken off). They have no vascular system and get all of their moisture and nutrients through their leaves, none through their roots or rhizoids that only anchor them to the soil.
I am the proud possessor of some Plagiomnium cuspidatum and one or more of the many species of the genus Brachythecium (Sievert kindly identified these for me from a photo), so I have a start. Sievert gets many of his mosses from woodlots to which he has access. Those without such a resource will need to purchase plants. He recommends Mountain Moss Enterprises of Pisgah Forest, North Carolina and Moss Acres of Honesdale, Penn. as reliable suppliers.
How to Choose
Identify your conditions (moisture, dappled sun, shade, climate zone, etc.) and find out what different mosses need. There is some disagreement about whether pH levels should be considered. Sievert thinks they may have some influence even though mosses get nutrients through their leaves. Suppliers should provide information about conditions that their plants require. We lucky ones with volunteer mosses know they have chosen a spot by themselves.
Trays of Moss Can Be Pricey
A way to stretch the budget requires some faith, but Sievert has heard reports of success with putting moss and an equal amount of buttermilk in a blender and liquefying them until the mixture resembles a thick milkshake. This can then be painted on any rough surface – rocks, wood, concrete or the outside of a container. Keep the object in the shade and mist it with water several times a week. Moss should begin to appear in a few weeks. Annie Martin of Mountain Moss pooh-poohs this idea so caveat emptor.
To grow on rocks: Hedwigia ciliata, Anomodon attenuates. For containers: Anomodon rostratus (hard to find, maybe impossible in Illinois), Plagiomnium cuspidatum (easily found in the Midwest). For damp, shady areas: Thuidium delicatulum, Climacium americanum (both can be found if you look enough). For sunny areas: Bryum caespiticium, B. argenteum, Ceratodon purpureus (all found in Illinois in many places, the first two on sidewalks and concrete areas, the last on gravel drives, etc.)
How to Plant
This really got my attention. Sievert glues sheets of moss to his limestone rocks with silicone caulk. Planting in the ground or in containers is more straightforward. He cautions, “I am quite sure that it is important to mimic the original soil substrate as closely as possible. My first effort at moss gardening was a complete failure as I took moss off a cedar shake roof and tried to grow it on the ground.” He uses the same technique for growing on the ground or in containers. After transplanting, he waters the moss one time, then presses it down in order to make good contact so new rhizoids (attachments sent into the substrate) grow. He advises patience. “It probably varies with the species, but my favorite, Anomodon rostratus, takes from one to three months to attach itself fairly tightly.” Annie Martin claims that mosses must be kept moist with daily watering for at least two months after planting. Sievert says, “I don’t and it works just fine. I’m afraid of fungus and mildew with frequent watering.” In essence, don’t let new moss go completely dry.
Care After Planting
Sievert is a hands-off gardener. He never fertilizes his mosses. He has so many containers and so much moss growing on rocks and in the ground that he doesn’t water. He’s fine with letting his mosses go dormant when they get dry. These clever plants can go dormant for long periods and bounce back into lush life at the first shower. To prevent dormancy and its attendant brown appearance, water often in dry periods. Sievert doesn’t protect his mosses in the winter. Not even the ones in containers. “These guys are tough as nails,” he says. “They can survive the worst winters.” Asked about the problem of cracking containers in winter, he conceded that the plants were not a worry but their housing might be. Look for winter-tolerant pots.
Mosses have no insect problems, and there is only one disease problem, caused by a Phthium fungus. Occasionally birds or animals may disturb them. The only time-consuming requirement in growing mosses is the removal of weeds and debris. Not so very demanding for casual moss growers. A considerable headache for Sievert.
Listening to Sievert wax lyrical about the moss gardens he has tended and visited, I made sure that he keeps his own garden maintenance simple in order to have the time to enjoy the tiny glories of the plants themselves. He gets down on his knees to appreciate their structure. “Looking down on them from full height is like seeing something from an airplane window,” he says. He talks about his objective in creating a moss garden: “Inspiration from nature but not copying nature.”
The best time to view a moss garden, he suggests, is early on a sunny morning after a rain when everything is fully hydrated. I’m hoping to find one of those mornings this year. Me in my pajamas with a cup of coffee and maybe my magnifying glass. On my knees in the front yard. Hope the neighbors aren’t watching.
Susan Crawford writes freelance travel and garden stories as well as fiction. She has published in The New York Times and a number of other journals. She is finishing up her first novel.