St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4
Grass Family
Poaceae, subfamily Panicoideae, tribe Paniceae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Common or 'Palmetto' (given the broad blade and light green hue)
Hardiness Zones
USDA Zones 8-10. Poor cold tolerance; goes dormant and turns tan/brown after the first hard frost. Thrives in high heat and humidity.
About This Grass
A coarse-textured, low-growing turfgrass that forms a dense, carpet-like sod. It features a distinct light to medium green color and exhibits relatively slow vertical growth but aggressive lateral spread. When unmowed, it produces short, terminal flower spikes.
Blade Characteristics
Coarse blades (8-10mm wide), flat with a distinctively rounded or 'boat-shaped' tip. Vernation is folded in the bud. Ligule is a fringe of short hairs; auricles are absent. The collar region is narrow and continuous.
Root System
Extensive fibrous root system primarily established from nodes along thick, aggressive stolons. High thatch-forming tendency; moderate establishment speed from sod or plugs.
Growing Information
Origin Region
Native to the Gulf of Mexico region, West Indies, and Western Africa; well-adapted to the humid Southeast US coastal plains.
Growth Habit
Stoloniferous; spreads via creeping above-ground runners that form a dense, thick mat.
Sunlight & Water Needs
Full sun to partial shade (one of the most shade-tolerant warm-season grasses). Requires high water availability; low drought tolerance compared to Bermuda grass. Prefers well-drained, slightly acidic to neutral soils.
Mowing & Maintenance
Ideal height: 2.5 to 4.0 inches. Requires frequent mowing to manage thatch. Fertilization: 2-4 lbs N per 1000 sq ft annually. Requires periodic dethatching and aeration. High maintenance level.
Special Characteristics
High shade tolerance, good salt tolerance (excellent for coastal areas), moderate wear tolerance, but slow recovery from damage. Susceptible to Chinch bugs and Gray Leaf Spot.
Ecological Information
Introduced/Naturalized in the US. Provides excellent soil stabilization and erosion control due to dense matting. Low wildlife value; can be invasive in native coastal habitats if not managed.