Thomas J. Koske | 4/19/2005 10:28:27 PM
Centipede lawns are very popular in Louisiana. It is called the "lazy man’s grass," and for good reason, according to LSU AgCenter horticulturist Dr. Tom Koske.
Centipede grass grows slowly and requires little maintenance. "If we take too-good care of it, we may ‘kill it with kindness,’" Koske says.
The grass is not without its problems, however. Centipede decline is a complex, lethal syndrome usually expressed by large dead or very chlorotic yellow patches found in spring. Lawns may green up and die out or simply never come out of dormancy.
Centipede decline causes are not well understood, but several relationships have been noticed by turf researchers. The grass should not be overfed, grown on heavy thatch or be left too dry.
The grass survives in acid soils of ph 5, but it prefers the higher fives. It will do well and not decline in ph 6.7 but will be lighter in color.
"That does not mean, however, you can bring out the green with more fertilizer," Koske says, noting that centipede needs only 1 to 2 pounds of nitrogen per season. More than 2 pounds of N may bring decline. Ask your lawn service how much fertilizer (N, P2, O5, K) it applies each year and when it starts and stops. Match the amount of potassium to that amount of N applied.
Thatch is very dangerous for centipede, as is a tall mowing height. It grows well when mowed at 1 to 1 1/2 inches. Remember to follow the 1/3 rule of cut. That is, don’t cut off more than the top third of the leaf. Short cuts require more frequent mowing. Tall cuts, excessive thatch and fall nitrogen fertilization all condition centipede for more winter freeze damage. If extra green is required, try a foliar spray of an iron chelate, the LSU AgCenter horticulturist recommends.
Drought stress is also implicated in decline. Ensure adequate moisture in spring, and maintain this for good summer growth. Centipede is one of the most drought-sensitive turfgrasses around.
"You will get more and better turf spread and thickening with good irrigation than with extra fertilizer," Koske says.
Look for Gardening and Get It Growing links in the Feature section of the LSU AgCenter Web site: www.lsuagcenter.com. Related yard and garden topics are available by contacting an extension agent in your parish LSU AgCenter office.