BOSTON — There's something irresistible about moss that begs you to run your fingers over it.
Recently gardeners in the United States - perhaps taking a clue from the exquisite moss gardens in Japan - have begun to appreciate the soothing effect and visual appeal of a velvety swath of uninterrupted green.
There are 15,000 species of moss, each having specific yet humble tastes.
Some cling to rock, others cover tree bark. It often pops up in nooks and crannies that other greenery avoid. Whatever its appeal, it is growing quickly as gardeners learn to cultivate their own magic carpets.
"It's really caught on in a big way in the United States in the past two years," says Holly Shimizu, horticulturist at the Lewis Ginter Botanical Garden in Richmond, Va.
Some landscapers now specialize in moss gardens, and nurseries are scrambling to keep starter patches in stock.
The Garden in the Woods in Framingham, Mass., offered a symposium on moss gardening last year and expected 35 people to attend. Some 125 participants showed up, with another 75 on a waiting list.
Moss gardening is not new to the Japanese, who have used it in their tidy gardens for centuries. Enthusiasts consider the premier example to be the blanketed grounds of the Saihoji Temple in Kyoto. Zen Buddhist monks have long valued moss for its simplicity and neatness and it is often found in meditative gardens.
Moss dates back about 400 million years. It has no roots or vascular system - nutrients are transmitted cell to cell.
Moss comes in all shades of green as well as yellow, rose, burgundy, dusky blue, silver, black, and even a glow-in-the-dark variety called "goblin's gold."
In winter when other plants sleep, moss is still perky since it is an evergreen that is photosynthesizing all year long. It is especially plentiful in shady, humid areas, around trees, rocks and along streams.
For moss tourism in the US, visit gardens at the Bloedel Reserve on Bainbridge Island in Washington or the Bayard Cutting Arboretum on Long Island, in New York. Some botanical gardens feature mossy areas, as part of Japanese gardens. Prime viewing times are spring and autumn, when rains and moist conditions makes moss happiest.
Moss may to grown at home, in containers, around the yard, or even as a replacement for lawn. "It doesn't have to be mowed, and can make a tapestry through which wildflowers and other little treasures will come and go," says Ms. Shimizu.
Contrary to popular belief, moss can be sat and walked on. When cultivating moss, choose varieties that will thrive under the conditions present - soil, sun, and moisture are prime considerations.
Three ways to grow moss are to encourage some that is already there to expand, to replant imported clumps, or to grow it by scattering spores.
A few varieties may be ground up in the blender with some buttermilk and will regenerate when sprinkled over soil.
Mosses prefer soils with a pH level of 5.5 or less. To make soil more acidic, spritz it with one quart of buttermilk mixed with one gallon of water), rhododendron fertilizer, or sulfur powder (2-1/2 pounds sprinkled over 100 square feet of soil).
Moss that has been transplanted requires a light daily watering for the first year, weekly thereafter. It does not like to be smothered by weeds and fallen leaves, so these should be removed if the moss is to be encouraged to spread.
Squirrels and birds are enemies of moss and will dig through it or make off with it altogether. Pegging down one-inch square netting discourages them.
Gathering moss from the wild disturbs local habitats. Christine Cook, a moss landscaper in Connecticut, recommends calling developers and letting them know you will be happy to clear moss from areas they are about to bulldoze. Or, she says, "find people who hate moss and tell them, 'I'll be over tomorrow with my trowel.' "