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' (Standard broad-leaf appearance)
Hardiness Zones
USDA Hardiness Zones 8-11; poor cold tolerance; will go dormant (brown) if temperatures drop below 55°F consistently.
About This Grass
A coarse-textured, low-growing turfgrass that forms a dense, thick carpet. It has a medium to deep green color and retains its color well in warm weather, turning brown during winter dormancy in cooler zones.
Blade Characteristics
Coarse blade width (8-10mm); folded vernation; rounded or blunt 'split' tips; broad, flat blades; constricted collar; short fringe of hairs for a ligule; auricles are absent.
Root System
Relatively shallow fibrous root system originating from stolon nodes; high thatch-forming tendency; moderate establishment speed; fair drought tolerance once established.
Growing Information
Origin Region
Native to the Gulf Coast region, Caribbean, and Mediterranean; adapted to subtropical and tropical coastal climates
Growth Habit
Stoloniferous (spreads via aggressive, thick above-ground runners/stolons); mat-forming
Sunlight & Water Needs
Partial Sun to Full Sun (one of the most shade-tolerant warm-season grasses); requires at least 4-6 hours of light; high water requirements; prefers well-drained, slightly acidic to neutral soils.
Mowing & Maintenance
Ideal height 2.5 to 4.0 inches; weekly mowing in peak season; fertilization 3-5 lbs N per 1000 sq ft per year; moderate to high maintenance due to water and pest needs.
Special Characteristics
Excellent shade tolerance for a warm-season grass; high salt tolerance (good for coastal areas); poor wear tolerance due to succulent stolons; susceptible to Chinch Bugs and Large Patch disease.
Ecological Information
Commonly introduced as a lawn turf; provides soil stabilization in sandy coastal areas; low wildlife value; non-invasive in most upland areas but can dominate garden beds via stolons.