The Low Down on Centipede Grass
Few species of plants raise as many questions for the citizens of Lee County as Centipede grass. Centipede is a warm season species of turf grass that is commonly grown here in the South-central portion of North Carolina that is proclaimed as a short; slow growing turf grass that requires infrequent mowing, low maintenance and little fertilizer. However, centipede can be notoriously difficult to grow compared to some other species of turf. Many factors can impede healthy growth such as; soil compaction, foot traffic, and heavy shade. Centipede grass can also be plagued with some insect and disease issues, the most common recently here in Lee County, being centipede grass decline.
Centipede decline has been occurring at a seemingly alarming rate this spring here in Lee County. Centipede decline entails a failure to green up in the spring followed by further decline and eventual death in the late spring and early summer. A multitude of factors can lead to centipede decline, but the most common ones are improper nutrition, poor cultural practices, and soil and water issues. Any of these problems or a combination of them may very well cause one’s centipede to fail. This coupled with other pests and disorders has been giving lawn caretakers and homeowners fits this spring.
Thankfully for anyone who manages a lawn there are corrective and preventative measures. As always, prevention is the best tactic to use in order to avoid any problems in your lawn or landscape especially when centipede decline is involved. To prevent centipede decline the nutritional, cultural, and soil and water needs of the grass must be met. Centipede grass is no different than any other plant in that it will be much less susceptible to pests and disease when it is healthy. If it is too late to prevent centipede decline corrective measures may be taken. These generally involve changing your fertilizing regime as well as improving cultural practices, soil management, and watering practices.
Generally, when I see a case of centipede decline nutrition is to blame. Surprisingly, over fertilization and not under fertilization is often the cause. Centipede grass does not need to be fertilized before the month of June and if it is harm can be done to the lawn. Also, make sure to use a phosphorus free fertilizer as centipede does not use much phosphorus and can actually be harmed by it. Finally, take care to not over apply nitrogen. Centipede uses less nitrogen than most other grasses and too much can cause the color of the grass to change and heavy thatching to occur.
Poor cultural practices can also lead to centipede decline. Keep your centipede mowed to approximately 1-1.5 inches. Also make sure that you are removing no more than one-third the total length of the blade each time you mow. Excessive thatching can also be quite a problem for centipede grass. Thatching is the buildup of dead and decomposing plant material on the surface of the soil. Thatch can harm the grass by impeding the flow of air, water, and nutrients to the roots. Thatch layers can also harbor insects and disease causing fungus and bacteria. In order to prevent the buildup of excessive thatch, aerate regularly and avoid excess pesticide use that may kill the organisms that decompose the thatch layer. Raking and power raking are effective means of dethatching if thatch is already a problem.
The last piece of the centipede grass decline puzzle is soil and water management practices. To keep your centipede happy, maintain a soil pH that is between 5.0 and 6.0. Improper pH is a common mistake made when growing centipede grass, as centipede requires a lower pH than most other types of grass. Also make sure that the soil is well drained, otherwise the roots and in turn the overall health of the plant may be compromised. I would highly recommend conducting a soil test every 2 or 3 years so that you can make better soil management decisions.
Be sure to not over water centipede grass either. Excess irrigation will produce a weak root system that is unable to cope with any amount of water stress. Centipede grass does best on around an inch of water per week in most soils, but may require slightly more in sandy soils. As with other grasses irrigating at night is not a bad idea for centipede grass because it wastes less water.
Although centipede decline may sound like the end of the world for lawns everywhere do not be alarmed. With proper management practices and preventative measures centipede grass is still a good choice for a thick, healthy, and low maintenance lawn. A healthy lawn is much less susceptible to centipede grass decline as well as any other pests and diseases. Remember that prevention is one of the most important ways to avoid problems in the lawn and garden and that sound management practices are the best prevention out there for centipede grass decline.
For more information on Centipede Grass and Centipede Decline, contact N.C. Cooperative Extension, Lee County Center (919-775-5624).
Alec Check is doing a Horticulture Internship with North Carolina Cooperative Extension in Lee County this summer.