Covering Ground

Source: www.TurfMagazine.com

Moss is a low-maintenance alternative for turf in shady areas

A Japanese garden landscape with moss.

Sometimes it’s best to give up on turf—that is, give up trying to make it grow in shady, moist or hard-to-grow areas.

However, giving up on turf doesn’t mean giving up on a lush, green landscape. While there are several good ground cover choices, one little-used, but highly effective and attractive alternative to add some green is moss.

“Once established, moss is low maintenance; you don’t need to water, fertilize or cut it,” says Al Brenner, president and owner of Moss Acres (www.mossacres.com) a Honesdale, Pa.-based company that sells a variety of moss species to consumers and turf and landscape professionals.

Moss, in fact, can be one of the hardiest plants in the landscape once it is established. Bryologists, scientists who study moss, don’t know exactly when it first appeared, but some date moss back 350 to 700 million years ago; some scientists believe moss was the first type of plant to exist on land. Moss, which gets its nutrients from the air (it is rootless), requires nothing more than shade, acidic soil and moisture to thrive.

A flagstone walkway using Hypnum (sheet moss) between the stones. This is a common application of moss.

“In areas where other plants won’t do well, and you want a carpet [of green], moss is the ideal candidate,” says Brenner, who has extolled the virtues of moss on HGTV with his father, David Brenner, also a moss advocate, who has had an established 2-acre moss garden at his Pennsylvania home for 45 years.

Moss types for landscaping

There are 15,000 species of moss, 1,200 of which are native to North America. Moss is found everywhere on earth and can tolerate a wide range of conditions, from very hot to very cold, from sunny to shady conditions.

Brenner has narrowed down the types of mosses he offers to just four, which he characterizes as the best for use in North American landscapes, and are easily transplanted.

“We’ve fine-tuned which types are better for which sites, but it is still a guessing game,” admits Brenner. Still, his company cites a 90 percent success rate.

“Provided you put [the moss] in the shade and keep it moist until it is established, it will do well,” he says. Hot and dry environments do require deep shade and maybe even irrigation for moss to survive relocation shock, says Brenner. “We’ve even tricked the moss to doing well in California, Florida and Texas. Our mosses are not indigenous to those areas, but in the right conditions, it will do well.”

It is best to try smaller quantities of the four mosses that Moss Acres carries to see how it adapts to a particular area before deciding which variety to use. The company offers a Moss Sampler Set, which includes a sample of each variety, including 10 square feet of Hypnum moss, and one clump each (about 1 square foot) of Hair Cap moss, Rock Cap moss and Cushion moss.

Getting moss to grow

First, select an appropriate location with adequate shade. Some varieties will tolerate dappled sunlight, but most will not thrive in full sun. Then, remove any weeds or other vegetation from the site. Make sure the pH of the soil is right. Moss will thrive in a pH between 4.5 and 6.0. You can amend the soil with liquid sulfur or aluminum sulfate if the pH is too high.

Once the soil is ready, it needs to be thoroughly watered until is it soup-like. Press the moss down in sections into the soil firmly so there aren’t any air pockets underneath. While moss gets its nutrients from the air, it does need to anchor into the soil so it does not get dislodged. The moss needs to be watered regularly for the first two to three weeks after planting (but don’t allow standing water, which will allow it to rot). Spring or fall transplanting is ideal. Once the moss is established (after about two months), it will never need to be irrigated. If a dry spell occurs, it simply goes dormant and will dry out until the next rainfall, when it will go green again. It will not need fertilization or pesticides, and deer will not eat it.

Moss Acres offers a sampler of moss with the four varieties that it sells.

Best Places to Plant Moss

While moss is hardy, it does need certain conditions to thrive, particularly when it is first planted. Moisture and shade are requirements even for varieties that tolerate sun.

Moss that must tolerate heavy foot traffic along with sunlight might not do well, Brenner notes. “As long as the moss is damp, it is fine to walk on, except never in high heels,” he says.

The moss also must be cleared of leaves, pine needles and other debris, which will suffocate and eventually kill the moss. To make leaf cleanup easier, Brenner recommends a .25-inch black mesh netting, which should be put down before the leaves start to fall, and then simply rolled up once all the leaves have fallen off the trees.

Moss can be used between flagstones or surrounding a walking path, in patios, under most trees and around water features. You will need to decide how the moss will be used before deciding on the variety that will work best.

A Japanese garden landscape with waterfalls, using moss as a ground cover.

For example, sheet moss is great for walkways since it is resilient, and, because it is low growing, it is the best choice for a “moss lawn.” This type of moss can also be ground up and sprayed in large areas for easier application. By grinding sheet moss into. 25 to .5-inch fragments, there are two advantages: the amount of coverage area is increased three to four times, and breaking apart dry moss signals the plant to enter a growth phase once it hits moisture. This type of application is ideal for large projects where the client wants an “instant green carpet” of moss.

Buying moss on a large scale

Moss doesn’t come cheap. Prices range from $4 to $10 per square foot, depending on the variety and quantity purchased; although, ground-up sheet moss can end up costing one-third of that.

“If you do a very large area, it can get very expensive,” says Brenner. Most landscapers use moss for specialty gardens and not to cover acres of land. Large swaths of land are usually done incrementally, which is the best way to establish a moss lawn.

“Moss can be unpredictable, so it is best to start with a small area and see how it does on the site, instead of doing a huge area right off the bat,” says Brenner.

Moss does spread—some varieties spread quicker than others. Some landscapers may opt to “checkerboard” the pieces and allow it to spread on its own.

Brenner says his company is well-versed in larger installations and guiding landscapers (by telephone) through the steps of successfully installing moss for their clients.

“Landscapers’ clients are usually the ones who ask for moss, but a lot of landscapers just don’t have the time to source it and may not always understand how to properly establish it,” he says. “The fragments need to be babied, either by the landscaper or homeowner. If you lay it out and walk away from it, chances of it taking are less.”

Moss can’t be used everywhere, but it is a good addition to a landscapers’ tool­kit for problem areas. “If you have a site that’s shady and moist, think of moss,” says Brenner. “It is tough stuff, and, used in the right location, landscapers can have great success with it.”

Cushion moss has a light green color with a silvery-white cast to it.
Hair Cap moss has soil anchoring structures that closely resemble and function like roots.

Ideal Moss Types for Landscaping

Information adapted, with permission, from Moss Acres’ Web site:
Sheet Moss (Hypnum): A versatile, low-growing moss with a high transplant success rate. Hypnum thrives in shade, but will also tolerate dappled sunlight (not extended direct afternoon sun). The color is medium green. This moss is available by the square foot or pre-ground, can tolerate some foot traffic and is the easiest to work with. These unique shade plants are ideal as a ground cover between stepping stones, patio stones or any light to medium foot traffic area. Because of its low growth habit, Hypnum is the ideal companion plant for highlighting low-growing plants, such as evergreen ground covers and native wildflowers. It is also the moss of choice for “moss lawns” or moss paths.

Rock Cap Moss (Dicranum): This variety is typically found growing on top of rocks and boulders in the wild. It is dense and medium to dark green in color. It transplants well into shady areas and is a good selection for rock gardens and has been used in Japanese gardens for centuries. It is extremely hardy and survives harsh conditions.

Hair Cap Moss (Polytrichum): Haircap moss has soil anchoring structures that closely resemble and function like roots and must be shipped with soil attached. Haircap moss prefers medium shade to partial sun and likes a well-drained soil. It is shipped in clumps.

Cushion Moss (Leucobryum): Prefers sandy soil, likes shade, but can tolerate partial sun. This moss is a lighter green color with a silvery-white cast to it. It grows in a round cushion shape and is shipped in clumps. This is the tallest of the four varieties.

The author is a freelance writer from Keene, N.H.