St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, Subfamily Panicoideae, Tribe Paniceae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Common St. Augustine (likely due to medium-green color and visible seed head traits)
Hardiness Zones
USDA Zones 8-11. Excellent heat tolerance; poor cold tolerance, turning brown and entering dormancy quickly after the first frost.
About This Grass
A coarse-textured, low-growing grass with a vibrant green color. In the provided image, it shows a dense, matted growth habit interspersed with broadleaf weeds. Seed heads are inconspicuous spikes where florets are embedded in a thickened rachis.
Blade Characteristics
Wide blades (8-10mm), flat shape with rounded or 'boat-shaped' tips. Vernation is folded in the bud; light to medium green color. Ligule is a fringe of short hairs; auricles are absent.
Root System
Relatively shallow fibrous root system emanating from stolon nodes; high thatch-forming tendency; moderate establishment speed from sod or plugs.
Growing Information
Origin Region
Native to the Gulf Coast region, Caribbean, and Africa; well-adapted to tropical and subtropical coastal climates.
Growth Habit
Stoloniferous; spreads via thick, creeping above-ground runners that form a dense, carpet-like mat.
Sunlight & Water Needs
Full sun to partial shade; possesses the best shade tolerance among warm-season grasses. Requires frequent watering (1 inch per week) and prefers well-drained, slightly acidic to neutral soils.
Mowing & Maintenance
High mowing height (3.0–4.0 inches); weekly frequency. Requires 2-4 lbs of Nitrogen per 1000 sq ft annually. Moderate to high maintenance level due to water and pest needs.
Special Characteristics
Excellent shade tolerance for a warm-season grass; high salt tolerance (good for coastal areas); poor wear tolerance; susceptible to Chinch Bugs and Large Patch disease.
Ecological Information
Native to coastal regions. Provides soil stabilization but can be considered invasive in certain non-native sensitive wetland ecosystems. Often found with Dollarweed or Clover (as seen in image) if soil is wet or nutrient-deficient.