St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4
Grass Family
Poaceae, Subfamily Panicoideae, Tribe Paniceae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Standard (possibly 'Floratam' or 'Palmetto' based on blade width and stolon presence)
Hardiness Zones
USDA Hardiness Zones 8-11; poor cold tolerance; enters dormancy below 55°F; high heat and humidity tolerance.
About This Grass
A coarse-textured, low-growing grass that forms a thick sod. It maintains a deep green to blue-green color in growing season and turns brown during winter dormancy. Unmowed, it can reach 6-12 inches; maintained at 2.5-4 inches. Seed heads are spike-like racemes with seeds embedded in a thickened rachis.
Blade Characteristics
Coarse blade width (8-10mm); flat shape with a distinctively rounded or blunt 'boat-shaped' tip; dark green color; folded vernation in the bud; short, fringe-of-hairs ligule; absent auricles; constricted collar.
Root System
Moderately deep fibrous root system emerging from stolon nodes; slow to moderate establishment speed from sod or plugs; high thatch-forming tendency; creates a dense sod that recovers well from wear.
Growing Information
Origin Region
Native to the Caribbean, Gulf of Mexico, and West Africa; adapted to coastal regions and the Southern United States
Growth Habit
Stoloniferous (spreads by thick, creeping above-ground runners/stolons); forms a dense, coarse-textured mat
Sunlight & Water Needs
Partial sun to full sun; one of the most shade-tolerant warm-season grasses (needs 4-6 hours direct sun); high water requirement; moderate drought tolerance; prefers well-drained fertile soils with pH 5.0-8.5.
Mowing & Maintenance
Mowing height of 2.5-4.0 inches; weekly frequency during peak growth; 2-4 lbs Nitrogen per 1000 sq ft per year; high maintenance due to potential for thick thatch; aeration and vertical mowing often required.
Special Characteristics
Excellent salt tolerance (ideal for coastal areas); highest shade tolerance among southern grasses; poor traffic tolerance compared to Bermuda; prone to Chinch Bugs and Large Patch (Rhizoctonia).
Ecological Information
Introduced/Naturalized in the US; provides soil stabilization in sandy coastal areas; low wildlife food value but excellent cover for small insects/reptiles; non-invasive in non-tropical climates; often grown as a monostand.