St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4
Grass Family
Poaceae, Subfamily Panicoideae, Tribe Paniceae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Common or Floratam-type (likely a base cultivar given the coarse texture)
Hardiness Zones
USDA Hardiness Zones 8-11. It has poor cold tolerance and will enter dormancy (turn brown) after the first hard frost. It does not survive consistent sub-freezing temperatures for long periods.
About This Grass
A coarse-textured, low-growing turfgrass with a creeping growth habit. It is characterized by thick, succulent stolons that root at the nodes. The color is typically a vibrant medium to dark green, and the grass creates a dense, carpet-like sod that can effectively crowd out most weeds when healthy.
Blade Characteristics
Coarse blades (8-10mm width), short and rounded/blunt at the tips. The vernation is folded in the bud. Blades are smooth on both surfaces with a distinct midrib. The ligule is a fringe of short hairs, and auricles are absent. The collar is continuous and somewhat narrow.
Root System
Relatively shallow compared to Bermuda grass, but forms a dense fibrous network from stolon nodes. It has a high thatch-forming tendency and slow-to-moderate establishment from plugs or sod. Shallow roots make it less drought-tolerant than deeper-rooted warm-season grasses.
Growing Information
Origin Region
Coastal regions of the Gulf of Mexico, Caribbean, and Mediterranean; adapted to tropical and subtropical climates
Growth Habit
Stoloniferous (highly aggressive above-ground runners), forming a thick, dense mat
Sunlight & Water Needs
Partial sun to full sun (requires at least 4-5 hours of direct light). It is one of the most shade-tolerant warm-season grasses. Needs moderate to high water; prefers well-drained, sandy or loamy soils with a pH of 6.0-7.5.
Mowing & Maintenance
Recommended mowing height is 2.5 to 4.0 inches. Higher mowing promotes deeper roots. Fertilize with 2-4 lbs of Nitrogen per 1000 sq ft annually during the growing season. Medium maintenance level required to manage thatch and water needs.
Special Characteristics
High shade tolerance for a warm-season grass; excellent salt tolerance (suitable for coastal areas); poor wear tolerance due to the succulent nature of the stolons which can be crushed; susceptible to Large Patch (fungus) and Chinch Bugs.
Ecological Information
Introduced/Naturalized in the Southern US; provides soil stabilization in sandy coastal areas; low wildlife food value but provides cover for small invertebrates. Often sold as sod or plugs as it rarely produces viable seeds.