St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, subfamily Panicoideae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Floratam
Hardiness Zones
USDA Hardiness Zones 8-11; poor cold tolerance; enters dormant brown state when temperatures drop below 55°F; susceptible to winter kill in frost-prone areas.
About This Grass
A coarse-textured, low-growing grass with a lush, dark green color. It forms a thick, spongy mat that is highly effective at crowding out weeds. Seed heads are inconspicuous spikes with seeds embedded in a thickened rachis.
Blade Characteristics
Coarse width (>4mm), flat shape with a distinctively rounded or 'boat-shaped' blunt tip. Vernation is folded in the bud; ligule is a fringe of short hairs; auricles are absent. Typically a deep emerald to blue-green color.
Root System
Extensive fibrous root system primarily arising from stolon nodes; moderate depth; high thatch-forming tendency; slows to establish from seed (primarily established via sod or plugs).
Growing Information
Origin Region
Native to the Gulf of Mexico region, West Indies, and Western Africa; highly adapted to tropical and subtropical coastal climates.
Growth Habit
Stoloniferous; spreads aggressively via thick above-ground runners (stolons) to form a dense, carpet-like sod.
Sunlight & Water Needs
Partial Sun to shade tolerant (best shade tolerance among warm-season grasses); needs 4-6 hours of sun; high water requirements; moderate drought tolerance but wilts quickly without moisture.
Mowing & Maintenance
High maintenance; ideal height 3.5 to 4 inches; frequent mowing needed; 2-4 lbs Nitrogen per 1000 sq ft annually; requires regular dethatching and aeration.
Special Characteristics
Excellent shade tolerance for a warm-season grass; high salt tolerance (good for coastal areas); poor wear tolerance; susceptible to Large Patch (fungus) and Chinch bugs.
Ecological Information
Introduced/Naturalized in many regions; provides excellent soil stabilization and erosion control; low wildlife food value but provides cover; often found with Dollar Weed (Hydrocotyle) in moist conditions.