Moss in your lawn

Published 6:33 pm Friday, October 5, 2018

Bare areas appear in your lawn usually from a combination of conditions that are adverse to growing healthy grass. These include wet areas from poor drainage or excessive watering, excessive shade and soil that is compacted, too acidic and/or low in fertility. These conditions, moreover, are favorable for the growth of mosses that form a thick green mat on the soil surface.

Mosses have no seeds and reproduce from spores carried about by the wind. They do not kill grass but rather grow in those areas in the lawn hostile to growing grass. Removing of mosses can be achieved either mechanically or by use of chemicals (pesticides). If, however, the underlying conditions are not corrected, any removal will be temporary. Keep in mind that diseases, such as large patch and nematodes, and extreme cold can also cause bare areas to form in your lawn.

The objective in preventing the growth of mosses is to change the conditions to favor the growth of grass. If moss occurs in a shaded area, consider planting the most shade tolerant grass, St. Augustine, which requires at least four hours equivalent of direct sunlight. Both Zoysia and centipede will tolerate light shade, but Bermuda will not. Get a soil test through the Cooperative Extension (free, from April to November) to determine the soil pH and the need for adding any nutrients. If excessively acidic, increasing the soil pH by working in dolomitic lime to the top 4 to 6 inches of the soil will not kill mosses, but it will favor better growth of grass.

Remember that centipede does best in acidic soil (pH of 5.5), whereas the other warm-weather grasses do best at a slightly acidic pH of 6.0 to 6.5 (7.0 is neutral). Compacted soil inhibits the passage of water, nutrients and air to the grass roots, as well as limits needed root penetration. If compacted, the soil should be broken up and ample compost added and thoroughly incorporated down to a depth of at least 4 inches. In addition, periodic core aeration of the lawn will reduce soil compaction by removing plugs of soils. If a bare area has poor drainage, consider incorporating additional soil into low spots or installing a French drain.

Mosses can be removed from the affected areas by hand-raking or application of many pesticides, which must be applied according to the labels. The active ingredients to look for on the labels of some of the available pesticides include ferrous sulfate monohydrate, (Bonide Moss Max Lawn Granules, Scott’s Moss Control Granules for Lawns), potassium or ammonium salts of fatty acids (Bonide Moss Max, Safer Brand Moss & Algae Killer, Scott’s 3-in-1 Moss Control) and iron (Fe HEDTA) (Bonide Weed Beater Fe).

Alternatives to growing grass in shaded bare areas include covering with mulch (pine straw, shredded bark, crushed stone), letting the moss continue to grow as a low-maintenance ground cover if in a low-traffic area and installing a shade tolerant ground cover.

This information is given courtesy of Dan Bergbauer and the Extension Master Gardeners who are volunteers under the direction of the Beaufort County Cooperative Extension. Volunteers are available through the hotline to answer your questions concerning lawns, vegetables, trees, ornamentals, fruits, plant problems and diseases, pests, soil and many other horticulture issues relating to gardening in North Carolina. The hotline telephone number is 252-946-0111. You can leave a voice message at that number or email the Master Gardeners your questions at and a volunteer will return your call.

Gardening Calendar October

Lawn Care Tall fescue lawns can be seeded out this month. Mulch seeded areas with wheat or barley straw.
Be sure to water newly seeded areas.
There is no need to fertilize warm-season grasses like centipede and Zoysia.
Keep tree leaves from collecting on your lawn.
Preemergents herbicides can be applied to prevent winter annuals.


Fertilize spring flowering bulbs at planting with a balanced fertilizer.
Store fertilizer in a dry location so it can be used next spring.


If you don’t use your garden through the fall and winter months, consider planting a cover crop like annual rye, barley or wheat.
Plant spring flowering bulbs like daffodil, tulip, crocus and hyacinth.
Now is a good time to set out or transplant landscape plants. Be sure to “open up” the root balls on container plants.
Plant or transplant peonies this month.
Pansies can also be set out this month to add color to the landscape.


Cut back herbaceous perennials if an early frost kills the tops.
Any dead or diseased wood can be pruned out anytime of the year.
Weeds or unnecessary trees should be removed from the landscape.
Rootprune any plants you plan to move next spring.


Poa annua, henbit and other winter annuals can be controlled with the same preemergent herbicides used to control crabgrass.
Control the following woody weeds by spraying the recommended herbicide: trumpet creeper and blackberry.
Insects and diseases can be more severe in the autumn; keep a close eye on your fall vegetables.
Store pesticides in a secured, dry location that will not freeze. (Pesticides should be used sparingly! Use only when needed and always follow the label)

Other Activities

Prepare houseplants to reenter your home. Check them carefully for insects.
Clean up and put away unused gardening equipment so it will be ready for the spring.
Take soil samples of your lawn and garden.
Prepare bird feeders.
Dig and store summer bulbs like gladioli, dahlia and caladium before frost.
Dig sweet potatoes this month before frost kills the plants.
Start putting the leaves from your yard into a compost bin or use them as mulch in your garden.