Make a moss garden: No digging required

Submitted to Dorchester Banner/Laetitia Sands
A moss garden can be enhanced by a flowering evergreen shrub, a water feature and a statue, among other things.

Not long ago, I wrote about moss – how it had proliferated in the County since last year’s very wet spring and how some civilizations admired the tiny plant so much they devoted entire gardens to it.
This spring, as the unusually wet weather seems to be recurring, patches of moss which appeared in my yard for the first time have grown larger and look well on their way to creating a moss garden all by themselves, with no help from me.

As spring unfurls a dazzling display of pale green leaves and sweetly scented blossom many feet overhead, the green velvet carpets of moss spread further afield. Moss that wasn’t there a year ago now forms a pleasing backdrop to a group of pink and white tulips. Moss makes a soft bed on which lie small twigs and branches knocked from the trees by violent wind last week.
What would it take to make the moss growing in my yard or yours, or somewhere else, into a genuine moss garden or moss lawn?
“Why would you want to?” I imagine a reader muttering. For one thing, it looks beautiful, in my humble opinion. And remember that green, the main color of moss, is the most relaxing color to look at – an important consideration during the stressful coronavirus pandemic we’re living through.

Climate change
Another good reason: If you’re worried about climate change and the future of our precious planet as a home for life as we know it, not a frying pan, consider that moss absorbs many times more carbon dioxide – the greenhouse gas – than does grass. Moss can become a gardener’s personal weapon in the battle to prevent the climate from becoming too hot for comfort.
Making a moss garden involves no digging or pruning and scant maintenance, once established, apart from occasional weeding. All it needs is more watering than turf or traditional garden plants and possibly some adjustment to your soil chemistry, unless you plant a moss which matches the soil you already have. But that shouldn’t be difficult. Most mosses prefer acidic soil, the type we have in abundance in Dorchester.

It’s also useful to know which mosses can be propagated easily from moss fragments – the equivalent of grown from cuttings – and which will tolerate the particular light conditions of your yard. While most mosses prefer shade, some thrive in sun, too.
Some, like tree moss (climacium americanum), can help control erosion while others will soak up the excessive sogginess of waterlogged areas. Interestingly, some mosses grow sideways — for example, common tree apron moss (anomodon rostratus)—while others grow horizontally.
Where should one plant moss? It could grow in deep shade, for example under a tree where little else will grow. An interesting fact: Moss can live under a walnut tree, which no other plant can. Moss could grow as a lawn, instead of turf grass (no mowing needed).
It’s a natural for northern-facing areas, which tend to be cooler and retain more moisture than southern, eastern or western exposures. But some mosses will tolerate non-northern facing spots, as well.

Problem areas
Look at your yard. Do you have problem areas? Erosion on slopes can be alleviated by haircap moss (polytrichum commune), star moss (atrichum angustatum) and big star moss (atrichum undulatum). For low-lying, soggy areas where water pools after rain, rotting the roots of many plants over time, consider moisture loving moss such as “many fruited thread moss” (plagiomnium ciliare) or tree moss, mentioned above.
Peat moss (sphagnum palustre), one of more than 200 species of sphagnum moss, likes wet conditions, too. It grows quickly, up to 10 inches tall (giant, for a moss), and likes acidic, low-nitrogen soil. Do not apply fertilizer! Somewhat delicate, this moss looks nice along the edges of ponds and streams and dislikes being walked on.

Other mosses are perfect for a lawn because they don’t mind foot traffic. Star moss (atrichum angustatum) is one. It reaches ¾ inch tall, grows well from fragments and has a medium green color, enhanced by a bronze-orange color when in its reproductive (sporophytic) stage, which can be quite often. Big star moss (atrichum undulatum) is another. A lighter, translucent green, it reaches a height of ½ to 2 inches, grows quickly from fragments and does particularly well in wetter, acidic soil.
Fast-growing mosses include: Plume moss (fissidens dubius), which likes damp areas and lots of rain, Delicate fern moss (thuidium delicatulum) and two other sorts of fern moss, Hypnum curvifolium and hypnum imponens. The first hypnum has a beautiful texture. It’s thick and spongy, resembles dwarf ferns and is green, turning gold at times. The second one resembles brocade, does better in dry conditions and prefers well-drained soil. It favors decaying logs and woodland habitats (which one can recreate in a yard).

The right stuff
Moss for planting can be ordered from a moss nursery, known as a mossery, or harvested oneself — from an abandoned site, like a logged area, or a friend’s yard, for example. To harvest moss, starting at the edge of a colony (as a patch of moss is called), gently peel off a piece with your hands. If not planting it immediately, keep it moist in a shady, cool spot. Do not buy dried moss sold in bags or boxes at garden centers or stores. It may have been chemically treated or sprayed with dye.
You can plant moss in any season, but fall is best because the cool temperature and rain make for less stress on the transplants. Clear the planting area of weeds and debris, rake over the soil, lay down the moss fragments – green side facing up, of course – then water and walk on them.
To start with, moss needs to be watered several times a day, if possible, but for only two to five minutes each time. Use the mist setting of the hose and if you can’t water more than once a day, do so in late afternoon or at night.

As companion plants to moss, consider evergreen shrubs like rhododendron and azaleas, shade-lovers like bleeding heart, ferns and hosta, miniature narcissi and small, delicate native plants like eastern columbine.
As always, pull weeds – especially invasives — as soon as you spot them. I found skinny little tendrils of Japanese honeysuckle weaving through my wild moss patch, as if to disguise themselves and hide from the gardener’s eagle eye. In the meantime, happy gardening!
Editor’s Note: Laetitia Sands is a master gardener in Dorcheste.