St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4
Grass Family
Poaceae, subfamily Panicoideae, tribe Paniceae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Likely 'Floratam' or 'Palmetto' based on blade width and color
Hardiness Zones
USDA Zones 8-11. Poor cold tolerance; susceptible to winter kill in temperatures below 10°F.
About This Grass
A coarse-textured, low-growing turfgrass with a vibrant medium-to-dark green color. It is highly competitive, forming a thick sod that crowds out weeds. It maintains its color well into the fall but goes dormant and turns brown after the first hard frost.
Blade Characteristics
Coarse blades (>4mm wide), flat, with a rounded/obtuse tip. Vernation is folded in the bud. Ligule is a fringe of hairs; auricles are absent. The collar is continuous and constricted.
Root System
Relatively shallow fibrous root system supported by thick, woody stolons. High thatch-forming tendency; establishes moderately fast from sod or plugs.
Growing Information
Origin Region
Native to coastal regions of the Gulf of Mexico, the Caribbean, and West Africa; adapted to tropical and subtropical climates.
Growth Habit
Stoloniferous (spreads via aggressive above-ground runners), forming a dense, coarse mat.
Sunlight & Water Needs
Prefers Full Sun but has excellent shade tolerance (one of the best for warm-season grasses). Requires frequent watering during establishment and regular irrigation during dry spells; moderate drought tolerance.
Mowing & Maintenance
Ideal mowing height is 2.5 to 4.0 inches. Requires frequent mowing during peak summer. Fertilization: 2-4 lbs N per 1000 sq ft per year. High maintenance level due to water and pest needs.
Special Characteristics
Excellent shade tolerance compared to other warm-season grasses; high salt tolerance (good for coastal areas); poor wear tolerance; susceptible to Chinch bugs and Gray Leaf Spot.
Ecological Information
Introduced/Naturalized in the US coastal south. Provides soil stabilization in sandy coastal areas. Not considered invasive in managed landscapes but can spread into adjacent garden beds via stolons.