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 standard residential variety)
Hardiness Zones
USDA Hardiness Zones 8-11; poor cold tolerance; enters dormancy when temperatures drop below 55°F; high heat and humidity tolerance.
About This Grass
A coarse-textured, low-growing turfgrass that forms a dense, blue-green sod. It remains relatively low when mowed but can reach 6-12 inches if left unmowed. It turns brown during winter dormancy in cooler climates.
Blade Characteristics
Coarse blades (>4mm width), flat and wide with a distinct rounded or blunt tip. Vernation is folded in the bud; ligule is a fringe of short hairs; auricles are absent.
Root System
Moderately deep fibrous roots with aggressive thick stolons. It has a high thatch-forming tendency and slow-to-moderate establishment speed from sod or plugs.
Growing Information
Origin Region
Native to the Caribbean, Gulf of Mexico, and West Africa; adapted to tropical and subtropical coastal regions
Growth Habit
Stoloniferous (spreads via aggressive above-ground runners); forms a thick, carpet-like mat
Sunlight & Water Needs
Partial Sun to Full Sun (one of the most shade-tolerant warm-season grasses); needs 4-6 hours of light; high water requirements; moderate drought tolerance but wilts quickly without moisture.
Mowing & Maintenance
Ideal height 2.5 to 4.0 inches; weekly mowing; requires 2-4 lbs of Nitrogen per 1000 sq ft annually; high maintenance due to water and pest needs.
Special Characteristics
Excellent shade tolerance for a warm-season grass; high salt tolerance (ideal for coastal areas); poor wear tolerance due to thick stolons; susceptible to Chinch bugs and Gray Leaf Spot.
Ecological Information
Introduced/Naturalized in the US; provides soil stabilization; low wildlife value beyond cover; can be invasive in sensitive coastal ecosystems; often blended with southern weeds like the Centella asiatica seen in the image.