St. Augustine Grass
Stenotaphrum secundatum · Warm-season (C4), Perennial
Grass Family
Poaceae, Subfamily Panicoideae, Tribe Paniceae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Common St. Augustine (likely, based on wide blades and coarse texture)
Hardiness Zones
USDA Hardiness Zones 8-11; poor cold tolerance; enters dormancy and turns brown when temperatures consistently drop below 55°F.
About This Grass
A coarse-textured, low-growing grass with a vibrant green to blue-green color. It features thick, succulent stolons that root at nodes. When unmowed, it can reach 6-12 inches; maintained, it forms a thick sod. Seed heads are spike-like racemes with seeds embedded in a flattened rachis.
Blade Characteristics
Coarse blade width (>4mm), reaching up to 10mm. Blades are flat with a distinct rounded or blunt 'boat-shaped' tip. Vernation is folded in the bud; ligule is a short fringe of hairs; auricles are absent; collar is broad and continuous.
Root System
Moderately deep fibrous root system originating from stolon nodes; high thatch-forming tendency; moderate establishment speed from sod or plugs (rarely from seed).
Growing Information
Origin Region
Coastal regions of the Gulf of Mexico, Caribbean, and Mediterranean; well-adapted to the Southeastern United States and California coastal areas.
Growth Habit
Stoloniferous (spreads via thick, creeping above-ground runners); forms a dense, carpet-like mat.
Sunlight & Water Needs
Partial sun to full sun (requires at least 4-5 hours); good shade tolerance compared to other warm-season grasses; high water needs; moderate drought tolerance but wilts quickly without moisture.
Mowing & Maintenance
Ideal height 2.5 to 4.0 inches; weekly frequency; 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 for a warm-season grass; high salt tolerance (ideal for coastal areas); poor wear tolerance; susceptible to Chinch Bugs and Large Patch (fungus).
Ecological Information
Introduced/Naturalized in the US; provides soil stabilization in sandy coastal soils; generally not invasive in non-wetland inland areas; often grown as a monostand rather than in mixes.