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 Floratam (likely based on coarse texture)
Hardiness Zones
USDA Zones 7-11. Poor cold tolerance; enters dormancy and turns brown when soil temperatures drop below 55°F.
About This Grass
A coarse-textured, low-growing grass that forms a thick, spongy sod. Leaves are typically dark green and remain green longer into the fall than other warm-season grasses. It produces short, spike-like seed heads but is primarily established vegetatively.
Blade Characteristics
Coarse blades (>4mm wide), flat with a rounded/obtuse tip. Leaves are folded in the bud (folded vernation). Ligule is a fringe of short hairs; auricles are absent. The collar is continuous and somewhat constricted.
Root System
Relatively shallow fibrous root system emanating from thick stolons. High thatch-forming tendency; moderate establishment speed from sod or plugs.
Growing Information
Origin Region
Native to coastal regions of the Gulf of Mexico, Caribbean, and Mediterranean; well-adapted to subtropical and tropical climates.
Growth Habit
Stoloniferous (spreads via thick above-ground runners); forms a dense, carpet-like mat.
Sunlight & Water Needs
Prefers Full Sun but has high shade tolerance compared to other warm-season grasses. High water needs; poor drought tolerance compared to Bermuda. Prefers pH 5.0-8.5.
Mowing & Maintenance
Recommended height 2.5-4.0 inches. Mowing frequency: weekly. High maintenance; requires 2-5 lbs Nitrogen per 1000 sq ft annually and frequent irrigation.
Special Characteristics
Excellent shade tolerance for a warm-season grass; high salt tolerance (good for coastal areas); poor wear tolerance due to spongy stolons; susceptible to Chinch bugs and Gray Leaf Spot.
Ecological Information
Introduced/Naturalized in the US. Provides soil stabilization in coastal sandy soils but can be aggressive, crowding out native species in favorable environments.