Centipede grass is a slow-growing perennial lawn that spreads by stolons. It is sometimes called China grass or Chinese lawn grass because of its Asian origins, but the centipede-like appearance of its stolons give it its more common name. Centipede grass is very easy to maintain and grows well in either full or partial sun. This adaptable grass is only susceptible to a couple of diseases, which are as easy to manage as the turf itself.
Two common diseases plague centipede grass: dollar spot and brown patch.
Dollar spot, as its name implies, develops spots that are light brown and 2 to 4 inches in diameter on the lawn. Brown patch often starts as a small spot and develops into a larger circle or sometimes horseshoe shape up to 2 feet wide.
Dollar spot is a fungal disease, caused by Sclerotinia homoeocarpa found in the grass' thatch. Brown patch is also a fungal disease which develops under the right growing conditions such as mild daytime temperatures (between 75 and 85 degrees Fahrenheit), excess moisture, and moderate evening temperatures (below 68 degrees F).
To control dollar spot, wait until the grass is dry (to avoid spreading the fungus) and cut no more than 1/3 of the grass' blade. Remove and dispose of the clippings. Avoid watering later in the day, even light sprinklings, which will cause the disease to advance. According to the University of Florida Extension, brown patch can be controlled by following a strict fertilization and watering program and mowing the grass higher during potential periods of outbreak.
According to the University of Rhode Island Landscape Horticulture Program, fungicides can be used to treat dollar spot, but its injury to a lawn does not typically warrant so. A number of fungicides are readily available at home garden centers such as benomyl and chlorothalonil. Homeowners should note, however, that products that contain chlorothalonil or thiophanate-methyl are ineffective when temperatures exceed 90 degrees F.