St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, subfamily Panicoideae, tribe Panicae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
'Floratam' (or standard common St. Augustine), featuring wide, coarse blue-green blades and vigorous stoloniferous growth.
Hardiness Zones
Thrives in USDA Hardiness Zones 8-10. Sensitive to frost and extreme cold, entering winter dormancy and turning brown when temperatures drop consistently below 50°F.
About This Grass
Forms a dense, coarse-textured, bright to blue-green turf with a thick spongy mat. Height can reach 6 to 12 inches if unmowed, but maintained at 2.5 to 4 inches. Produces flat, ribbon-like seed spikes at maturity.
Blade Characteristics
Coarse texture (>4mm wide), flat to folded shape with rounded or bluntly pointed tips, bright green to blue-green color. Vernation is folded in the bud. Features a short membranous ligule with a fringe of hairs, and auricles are absent.
Root System
Moderately deep fibrous root system originating from nodes on stolons. Tends to produce moderate thatch. Establishes relatively quickly from sod or plugs. Good wear recovery due to aggressive above-ground stolons.
Growing Information
Origin Region
Native to tropical and subtropical regions along the Gulf of Mexico, Caribbean, and Mediterranean. Widely cultivated in the southeastern United States.
Growth Habit
Stoloniferous (spreading aggressively above ground via stolons or runners), forming a thick, dense, coarse turf mat.
Sunlight & Water Needs
Requires full sun to partial shade (more shade tolerant than most warm-season grasses, needing at least 4 hours of direct sun). High watering needs for optimal appearance, fair drought tolerance by entering dormancy. Prefers moist, fertile soils with a pH of 5.5 to 7.5.
Mowing & Maintenance
Mow at 2.5 to 4 inches every 7-10 days during the growing season. High maintenance level requiring regular fertilization (2-5 lbs N per 1000 sq ft annually), periodic dethatching, and monitoring for pests like chinch bugs.
Special Characteristics
Fair to good shade tolerance compared to other warm-season grasses. Moderate traffic tolerance, excellent salt tolerance (ideal for coastal regions), susceptible to chinch bugs, take-all root rot, and sod webworms.
Ecological Information
Introduced/cultivated across the American Sunbelt. Provides good soil stabilization and erosion control on coastal sandy soils. Low invasiveness risk outside cultivated landscapes, serves as a standard residential turf ecosystem.