St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4
Grass Family
Poaceae, Panicoideae, Paniceae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Likely 'Floratam' or 'Palmetto'
Hardiness Zones
USDA Zones 8-10; poor cold tolerance; enters dormancy below 55°F; susceptible to winter kill in northern transition zones.
About This Grass
A coarse-textured, low-growing grass that forms a thick, spongy sod. It maintains a deep blue-green color in warm months and goes dormant (tan) in frost. Seed heads are inconspicuous, long spikes with seeds embedded in one side of a flattened rachis.
Blade Characteristics
Coarse width (>4mm), flat shape with a distinct boat-shaped or rounded tip. Medium to dark green. Vernation is folded in the bud. Ligule is a fringe of short hairs; auricles are absent. Collar is continuous and constricted.
Root System
Moderately deep fibrous roots originating from stolon nodes; high thatch-forming tendency; slow to moderate establishment from plugs or sod; excellent wear recovery via stolon growth.
Growing Information
Origin Region
Coastal regions of Africa, the Americas, and the Caribbean; common in US Gulf Coast and California
Growth Habit
Stoloniferous; spreads aggressively via thick above-ground stolons to form a dense, carpet-like mat
Sunlight & Water Needs
Partial Sun to Full Sun (one of the most shade-tolerant warm-season grasses); needs at least 4-5 hours of sun; moderate to high water needs; moderate drought tolerance but wilts quickly without moisture.
Mowing & Maintenance
Mowing height 2.5 to 4.0 inches; weekly frequency; 2-4 lbs N/1000 sq ft per year; high dethatching needs; medium maintenance level.
Special Characteristics
Excellent shade tolerance for a warm-season grass; high salt tolerance; susceptible to Large Patch (Rhizoctonia) and Chinch Bugs; does not tolerate heavy foot traffic as well as Bermuda grass.
Ecological Information
Native to tropical coastal areas; provides excellent soil stabilization in sandy coastal soils; generally non-invasive in non-tropical inland ecosystems; often used as a mono-stand rather than in mixes.