St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4
Grass Family
Poaceae, subfamily Panicoideae, tribe Paniceae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Standard species (visible traits suggest a common variety like Palmetto or Floratam based on blade width and stolon size)
Hardiness Zones
USDA Hardiness Zones 8-11. Poor cold tolerance; turns brown and enters dormancy when temperatures drop below 55°F. Susceptible to winter kill in northern transition zones.
About This Grass
A coarse-textured, low-growing grass with a vibrant medium-to-dark green color. It forms a thick, carpet-like lawn. In its unmowed state, it produces spike-like flowering racemes where the seeds are embedded in the rachis.
Blade Characteristics
Coarse blade width (usually >8mm), flat shape with a distinctively blunt or rounded boat-shaped tip. Dark green color. Vernation is folded. Ligule is a fringe of hairs; auricles are absent. The collar is broad and continuous.
Root System
Moderately deep fibrous root system originating from stolon nodes. High thatch-forming tendency due to saltatory stolon growth. Excellent sod-forming density but moderately slow to establish from seed (primarily established via plug, sod, or sprig).
Growing Information
Origin Region
Native to coastal regions of the Atlantic Ocean (Gulf of Mexico, Caribbean, Africa); widely naturalized in tropical and subtropical regions.
Growth Habit
Stoloniferous; spreads aggressively via thick, above-ground runners (stolons) to form a dense, mat-like sod.
Sunlight & Water Needs
Full sun to partial shade (one of the most shade-tolerant warm-season grasses). Needs at least 4-5 hours of sun. High water requirement; moderate drought tolerance but requires supplemental irrigation in dry periods. Prefers well-drained, slightly acidic to neutral soils.
Mowing & Maintenance
Recommended height 2.5 to 4.0 inches. Mowing frequency every 7-10 days. Requires 2-4 lbs of Nitrogen per 1000 sq ft annually. High maintenance level due to water and pest needs.
Special Characteristics
Exceptional shade tolerance for a warm-season grass. High salt tolerance (excellent for coastal areas). Moderate wear tolerance but slow to recover compared to Bermuda. Susceptible to Chinch Bugs and Large Patch (Rhizoctonia).
Ecological Information
Introduced/Naturalized in most of North America. Provides soil stabilization in sandy coastal areas. Low wildlife food value but provides cover for small insects and reptiles. Can be invasive in sensitive wetlands if not managed.