St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, subfamily Panicoideae, tribe Paniceae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Floratam (a widely used cultivar known for its coarse texture, blue-green color, and resistance to St. Augustine decline virus)
Hardiness Zones
USDA Hardiness Zones 8 through 10; excellent heat tolerance, poor cold tolerance (susceptible to frost damage and winter dormancy below 50°F), not suitable for the transition zone as a permanent lawn without winter overseeding
About This Grass
Forms a lush, dense, carpets-like turf with a coarse texture. Typically maintained between 2.5 and 4 inches in height. Bright blue-green to dark green in color during the growing season, turning brown or going dormant under frost conditions. Features flattened stems and rounded leaf tips.
Blade Characteristics
Coarse blade width (>4mm), flat shape, blunt or rounded tip, blue-green to green color, folded vernation in the bud, prominent midvein, membranous ligule reduced to a fringe of hairs, and absent auricles with a continuous collar region
Root System
Moderate depth fibrous root system anchored by thick stolons; moderate to high thatch-forming tendency, establishes moderately fast from sod or plugs, and provides good soil stabilization but moderate traffic tolerance
Growing Information
Origin Region
Native to the Gulf of Mexico region, coastal areas of the southeastern United States, and the Caribbean; well-adapted to tropical and subtropical climates worldwide
Growth Habit
Stoloniferous, spreading aggressively via robust above-ground runners (stolons) to form a thick, dense turf mat
Sunlight & Water Needs
Requires full sun to partial shade (most shade-tolerant of the warm-season grasses requiring a minimum of 4 hours of direct sunlight); moderate to high water needs; good drought dormancy capability but prefers moist, well-draining soils with a pH between 6.0 and 7.5
Mowing & Maintenance
Ideal mowing height ranges from 2.5 to 4 inches using a sharp rotary mower; mow every 7-10 days during peak season; fertilization needs 2-4 lbs N per 1000 sq ft annually; requires periodic dethatching and core aeration; medium-high maintenance level
Special Characteristics
Moderate wear tolerance, poor recovery from heavy damage due to stoloniferous growth, good salt tolerance making it ideal for coastal areas, moderate shade tolerance compared to other warm-season grasses, susceptible to chinch bugs and take-all root rot
Ecological Information
Introduced and naturalized widely across coastal subtropical regions; provides good soil erosion control and water filtration due to dense matting; offers limited wildlife habitat; often maintained as a monoculture lawn