St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, subfamily Panicoideae, tribe Panicae
Grass Category
Lawn/Turf Grass and Coastal Erosion Control
Variety / Cultivar
'Palmetto', 'Floratam', or 'Raleigh' (commonly cultivated varieties; 'Floratam' features longer and wider blades with purplish stolons)
Hardiness Zones
USDA Hardiness Zones 8 to 11. Sensitive to freezing temperatures and enters winter dormancy (turning brown) in colder parts of its range, recovering as temperatures rise in spring.
About This Grass
Forms a lush, dense, carpet-like turf with a coarse texture. Color is typically bright blue-green to apple-green during the growing season. Unmowed height can reach 6 to 12 inches, but it is typically maintained much lower. Produces flat, spike-like seed heads on terminal stems.
Blade Characteristics
Coarse texture with wide blades (4-10 mm wide), flat shape, blunt or rounded tips, bright green to blue-green color, folded vernation in the bud, prominent veins on the upper surface. Features a short membranous ligule with a fringe of hairs, absent auricles, and a continuous collar region.
Root System
Shallow to moderately deep fibrous root system originating from the nodes of the stolons. Tends to build up thatch moderately to heavily if over-fertilized. Establishes rapidly from sod or plugs, forming a tight sod that crowds out many weeds but has poor wear recovery compared to bermudagrass.
Growing Information
Origin Region
Native to coastal regions of the Gulf of Mexico, the Caribbean, and tropical regions worldwide. Cultivated extensively in the southern United States, particularly Florida, Texas, and along the Gulf and Atlantic coasts.
Growth Habit
Stoloniferous, spreading rapidly via thick, flat above-ground runners (stolons) to form a 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 water needs, especially during establishment and dry periods; fair drought tolerance by entering dormancy, but prefers consistently moist soils. Prefers well-draining soils with a pH between 6.0 and 7.5.
Mowing & Maintenance
Ideal mowing height ranges from 2.5 to 4 inches. Mowed every 5 to 7 days during peak growing season. Fertilization needs are moderate to high (2 to 5 lbs N per 1000 sq ft per year). Requires periodic dethatching and core aeration. Medium-high maintenance level.
Special Characteristics
Excellent shade tolerance for a warm-season grass, good salt tolerance (ideal for coastal properties), poor wear and foot-traffic tolerance, slow recovery from heavy damage, susceptible to chinch bugs, sod webworms, and take-all root rot.
Ecological Information
Introduced and naturalized in many tropical and subtropical regions. Provides soil stabilization and erosion control in coastal sandy soils. Serves as ground cover and minor habitat for small urban wildlife. Often planted as a monoculture lawn grass due to its inability to blend well with fine-textured companion grasses.