St. Augustine Grass
Stenotaphrum secundatum · Warm-season perennial, C4 metabolism
Grass Family
Poaceae, Subfamily Panicoideae, Tribe Paniceae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Common St. Augustine / Floratam (Likely based on coarse texture and light green color)
Hardiness Zones
USDA Zones 8-11. Excellent heat tolerance but poor cold tolerance; will go dormant and turn brown when temperatures drop below 55°F (13°C).
About This Grass
A coarse-textured, low-growing grass known for its rapid lateral spread. It features a medium-to-dark green color and forms a thick, spongy sod. When left unmowed, it can reach 6-12 inches; maintained, it is dense and lush with 2-3 flowered spikelets on a flattened rachis.
Blade Characteristics
Coarse width (8-10mm); flat shape with a distinctively rounded/obtuse boat-shaped tip. Color is bright to medium green. Vernation is folded in the bud; ligule is a short fringe of hairs; auricles are absent; collar is constricted and narrowed.
Root System
Moderately deep fibrous root system originating from stolon nodes. It has a high thatch-forming tendency and slow-to-moderate establishment from plugs or sod (rarely grown from seed).
Growing Information
Origin Region
Native to the Gulf of Mexico region, West Indies, and Western Africa; adapted to tropical and subtropical coastal regions including the Southern United States.
Growth Habit
Stoloniferous; spreads aggressively via thick, creeping above-ground stolons that root at the nodes to form a dense, carpet-like mat.
Sunlight & Water Needs
Partial shade to full sun (one of the most shade-tolerant warm-season grasses); requires at least 4-5 hours of direct sun. High water needs; poor drought tolerance compared to Bermuda, preferring moist, well-drained soils with pH 5.0-8.5.
Mowing & Maintenance
Mowing height of 2.5-4.0 inches; frequency of every 7-10 days. Fertilization of 2-5 lbs Nitrogen per 1000 sq ft annually. Requires periodic vertical mowing to manage thatch accumulation. High maintenance level.
Special Characteristics
Excellent salt tolerance (suitable for coastal areas), high shade tolerance for a warm-season grass, and good wear tolerance. Susceptible to Large Patch (fungus) and Chinch Bugs.
Ecological Information
Introduced and naturalized in many regions. Provides excellent soil stabilization due to dense matting. Can be invasive in sensitive wetland ecosystems but is generally valued for erosion control. Often grown as a monostand rather than in mixes.