Thomas J. Koske | 4/21/2005 9:09:07 PM
St. Augustinegrass (Stenotaphrum secundatum) is one of our two most popular lawn grasses in Louisiana. It is widely adapted to the humid Deep South, according to LSU AgCenter horticulturist Dr. Tom Koske.
St. Augustine is so popular, because it grows thick and tolerates a wide range of soil and environmental conditions as well as retaining some winter color better than any other warm-season grass.
Selections of the grass come in medium dark-green to blue-green and are all considered coarse leaved. Most cultivars tolerate shade and salinity well. They tolerate a wide range of soil types, but prefer a soil pH of 6 to 7. Growth is strong during warm-to-hot weather if moisture is ample and fertility is at least medium. This grass will also tolerate some compaction in heavier soils.
Koske says some disadvantages of this grass cause people to choose better adapted or more appealing turfgrasses. St. Augustine has a coarse leaf texture and requires a taller cut (2.5 inches to 3.5 inches). It is prone to thatch buildup and a spongy turf. Above hardiness zone 8B (Alexandria), it is likely to experience more freeze damage. This keeps a reasonable use limit ranging from Dallas to central Mississippi, over to central North Carolina and southward. It really thrives along the Gulf South Interstate 10 corridor.
The horticulturist says another big issue with this grass type is that it suffers from numerous pest problems. Several diseases can ruin an attractive lawn, and chinch bugs find it very attractive. Often its vigorous growth will repair damaged areas when growing conditions are good.
In addition, a number of weed problems may become apparent over time, but the coarse texture masks those problems for a while. "That is a good thing, because this grass is sensitive to many common herbicides and has few products labeled for use on it," Koske says.
Seedheads can be seen in mid to late summer. They are mostly inconspicuous, forming a short, thick spike. If plentiful, they may give the lawn an off color, but regular mowing minimizes this problem.
Quality St. Augustinegrass is always established vegatatively through 4-inch plugs, sod strips or solid sodding. Seed is very expensive and produces a lawn of questionable plant types. The years of breeding and selection have produced named cultivars that have the better qualities that we prefer and require. Popular varieties include Raleigh, Seville, Palmetto, Jade and Delmar; however, there are several others.
For information on related topics, look for Gardening and Get It Growing links in the Feature section of the LSU AgCenter Web site: www.lsuagcenter.com. Additional yard and garden topics are available from an extension agent in your parish LSU AgCenter office.