St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, Subfamily Panicoideae, Tribe Paniceae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Likely 'Floratam' or 'Palmetto' based on blade width and growth density
Hardiness Zones
USDA Hardiness Zones 8-11; poor cold tolerance; enters dormancy when temperatures drop below 55°F; prone to winter kill in northern transition zones.
About This Grass
A coarse-textured, low-growing turfgrass that forms a dense sod. It maintains a deep blue-green color in warm weather and turns tan/brown during winter dormancy. Unmowed, it can reach 6-12 inches; maintained, it is a thick, plush lawn.
Blade Characteristics
Coarse (8-10mm wide), flat blades with a blunt, rounded tip. Color is typically medium to dark green. Vernation is folded in the bud; ligule is a fringe of short hairs; auricles are absent.
Root System
Moderately deep fibrous root system emerging from stolon nodes; high thatch-forming tendency; moderate establishment speed from sod or plugs.
Growing Information
Origin Region
Native to the Gulf of Mexico, Caribbean, and Western Coast of Africa; well-adapted to tropical and subtropical coastal regions
Growth Habit
Stoloniferous (spreads via aggressive above-ground runners), forming a dense, thick mat
Sunlight & Water Needs
Partial Sun to Full Sun (one of the most shade-tolerant warm-season grasses); needs 4-6 hours of sun; high water requirement; moderate drought tolerance but wilts quickly without moisture.
Mowing & Maintenance
Ideal height 2.5 to 4.0 inches; weekly frequency; fertilization 2-4 lbs N/1000 sq ft/year; requires occasional vertical mowing for thatch control; maintenance level is Medium to High.
Special Characteristics
Excellent shade tolerance for a warm-season grass; high salt tolerance (ideal for coastal areas); poor wear tolerance due to succulent stolons; susceptible to Chinch Bugs and Large Patch disease.
Ecological Information
Introduced/Naturalized in the US; provides soil stabilization for coastal sandy soils; non-invasive in forest ecosystems but aggressive in residential landscapes; often grown as a mono-stand rather than a blend.