St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4
Grass Family
Poaceae, Panicoideae, Paniceae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Floratam (or similar wide-bladed cultivar based on coarse texture)
Hardiness Zones
USDA Zones 8-11; poor cold tolerance (susceptible to winter kill in northern transition zones); high heat and humidity tolerance; enters dormancy when temperatures drop below 55°F.
About This Grass
A coarse-textured, low-growing grass with a dark green to blue-green color. It forms a thick, spongy sod and produces short, spike-like seed heads on thick stems. It maintains color well in warm weather but turns tan in dormancy.
Blade Characteristics
Coarse blade width (8-10mm), flat shape with a distinct folded vernation; features a unique rounded or 'blunt' boat-shaped tip; ligule is a short fringe of hairs; auricles are absent; collar is constricted.
Root System
Mainly fibrous roots arising from stolon nodes; moderate depth; high thatch-forming tendency; establishes relatively quickly via sprigs or sod but slow from seed.
Growing Information
Origin Region
Coastal regions of North and South America, Africa, and the Caribbean; well-adapted to the US Gulf Coast and Florida
Growth Habit
Stoloniferous (spreads aggressively via thick, above-ground runners/stolons); forms a dense, carpet-like mat
Sunlight & Water Needs
Full sun to partial shade; among the most shade-tolerant of warm-season grasses; requires frequent watering during establishment and moderate to high water once mature; prefers slightly acidic to neutral soil (pH 6.0-7.5).
Mowing & Maintenance
High maintenance. Ideal mowing height is 2.5 to 4.0 inches; requires frequent mowing to prevent thatch buildup; fertilization needs 3-6 lbs of Nitrogen per 1,000 sq ft annually; requires regular aeration.
Special Characteristics
Excellent salt tolerance (ideal for coastal areas); moderate wear tolerance; highly susceptible to Chinch Bugs and Large Patch (Brown Patch) disease; very poor drought recovery compared to Bermuda.
Ecological Information
Native to coastal tropics; provides decent soil stabilization on sandy coasts; not considered invasive in residential areas but can displace native vegetation in wetland margins; often grown as a monoculture.