St. Augustinegrass Lawns

St. Augustinegrass is the most popular lawngrass in Florida. Its popularity can be attributed to its versatility. It produces a dark green, dense turf that will grow on a wide range of soils from sands to mucks and even the marl soils of south Florida. It has good salt tolerance and certain varieties will generally tolerate shade better than other warm-season lawngrasses.

Home gardeners are often faced with the problem of choosing a variety of St. Augustinegrass which will best fit their growing conditions and needs. The available varieties can be divided into normal growth habit varieties and semi-dwarf growth habit varieties. Normal growth habit varieties have a tall growth habit and should be mowed at a height of 3 to 4 inches. The semi-dwarf varieties have a low growth habit and should be mowed at a height of 1 1/2 to 2 1/2 inches. Other characteristics which differ among varieties are cold tolerance, shade tolerance, chinch bug and disease resistance, color, texture and density.

The following discussion of the growth characteristics of the available varieties may help you choose the best grass for your particular situation. The commonly available normal growth habit varieties are Bitterblue, Floratine, Floratam, Raleigh and Floralawn.

Bitterblue has very good shade tolerance but is not resistant to chinch bugs. It can produce a good lawn under proper management practices and pest control.

Floratine is a selection from Bitterblue that was released in 1962. It is finer textured, and its lower growth habit allows for closer mowing than Bitterblue. Floratine's other characteristics are similar to Bitterblue.

Floratam was released in 1973 by the University of Florida and Texas A & M University. Floratam's most outstanding attribute was its ability to resist chinch bug attack. However, there have been reports of chinch bug damage to Floratam, and a strain of chinch bugs has been recognized which can feed on Floratam. Floratam is a very vigorous, coarse texture grass with poor cold and shade tolerance. It is the preferred variety for open sunny areas.

Raleigh is a cold hardy variety released by North Carolina State University. It is a medium, green-colored, course textured grass which is susceptible to chinch bugs and brown patch disease. During peak summertime heat, Raleigh has been noted to yellow and not grow as fast as during cooler temperatures. Supplemental iron application can be applied to retain its green color during these periods.

Floralawn was released by the Florida Agricultural Experiment Station in 1986. This grass has very similar growth characteristics as Floratam. Floralawn should be grown in full sun to moderate shade under low to moderate fertility. As with Floratam, Floralawn can be severely damaged by a hard freeze.

In recent years, the fine textured, semi-dwarf varieties Seville, Jade and Delmar have become very popular. Seville has a dark green color, low growth habit, and performs well in sun or shade. However, it is susceptible to chinch bugs and webworm damage and is cold sensitive. Jade and Delmar have improved shade tolerance, shorter internodes, darker green color, and better cold tolerance than Seville. Jade has thinner leaf blades and better shade tolerance than Delmar. Delmar has better cold tolerance, and could therefore be grown in colder regions of Florida. Both are susceptible to chinch bugs, sod webworms, and brown patch disease.

One of the newest selections of St. Augustinegrass on the market is Palmetto. It is noted for its rapid spread and dark green color. It has finer leaf blade density compared to Floratam and a lower growth habit. Palmetto appears to have good cold-tolerance, some resistance to gray-leaf spot disease, but no notable chinch bug resistance.

By this time, you have probably come to the realization that the ideal St. Augustine lawngrass has yet to be developed. However, researchers at the University of Florida's Institute of Food and Agricultural Sciences continue to work to develop St. Augustinegrasses which will produce high quality, low maintenance lawns.