St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, subfamily Panicoideae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Likely 'Floratam' or 'Palmetto' based on blade width and color
Hardiness Zones
USDA Hardiness Zones 8-11. Poor cold tolerance; enters dormancy and turns brown when soil temperatures drop below 55°F.
About This Grass
A coarse-textured, low-growing grass with a vibrant blue-green color. It forms a thick, spongy sod and is known for its wide blades and blunt tips. Unmowed it can reach 6-12 inches; maintained turf is dense and resilient. Seed heads are inconspicuous spikes.
Blade Characteristics
Coarse blade width (>8mm), flat shape with a distinct folded vernation. Tips are characteristically rounded or boat-shaped. Color is medium-to-dark green. Ligule is a fringe of short hairs; auricles are absent; collar is broad and continuous.
Root System
Moderately deep fibrous roots originating from stolons. High thatch tendency due to thick stolon mat. Rapid establishment from sod or plugs but does not produce viable seeds.
Growing Information
Origin Region
Native to coastal regions of the Gulf of Mexico, Caribbean, and Mediterranean; adapted to tropical and subtropical climates
Growth Habit
Stoloniferous; spreads aggressively above ground via thick, creeping runners (stolons) to form a dense, coarse mat
Sunlight & Water Needs
Partial sun to full sun, though one of the most shade-tolerant warm-season grasses. High water needs; requires regular irrigation to maintain color. Prefers well-drained, slightly acidic to neutral soils.
Mowing & Maintenance
Ideal height: 2.5 to 4.0 inches. Mowing frequency: 7-10 days. Fertilization: 2-4 lbs Nitrogen per 1000 sq ft per year. High maintenance level due to water and dethatching needs.
Special Characteristics
Excellent shade tolerance for a warm-season grass, high salt tolerance (coastal suitable), moderate wear tolerance, susceptible to Large Patch (Rhizoctonia) and Chinch bugs.
Ecological Information
Introduced/Naturalized in the US. Provides excellent soil stabilization in coastal zones. Low wildlife value compared to native bunchgrasses. Can be aggressive in ideal climates.