St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, Subfamily Panicoideae, Tribe Paniceae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Likely 'Floratam' or 'Palmetto' based on blade width and typical residential use
Hardiness Zones
USDA Hardiness Zones 8-11; poor cold tolerance; enters dormant brown state when soil temperatures drop below 55°F; highly susceptible to winter kill in northern transition zones.
About This Grass
A coarse-textured, low-growing grass that forms a thick, carpet-like sod. It is characterized by its broad blades and wide, compressed stolons. Color is typically a deep blue-green when healthy. Seed heads are spike-like racemes with seeds embedded in a thick, flattened rachis.
Blade Characteristics
Coarse blade width (8-10mm), flat shape with a distinct rounded/obtuse tip. Color is dark green to blue-green. Vernation is folded in the bud; ligule is a short fringe of hairs; auricles are absent. The collar is constricted and smooth.
Root System
Moderately deep fibrous root system originating from stolon nodes; high thatch-forming tendency; slow to moderate establishment from plugs or sod; good wear recovery due to stoloniferous growth.
Growing Information
Origin Region
Native to coastal regions of the Gulf of Mexico, Caribbean, and Western Africa; adapted to humid tropical and subtropical climates
Growth Habit
Stoloniferous (spreads by vigorous above-ground runners), forming a dense, thick mat
Sunlight & Water Needs
Partial Sun to Full Sun (one of the most shade-tolerant warm-season grasses); requires at least 4-5 hours of sun; high water needs; moderate drought tolerance but wilts quickly without supplemental water; prefers slightly acidic to neutral pH (5.0-8.5).
Mowing & Maintenance
Ideal height 2.5 to 4.0 inches; frequency every 5-7 days during peak growth; fertilization 2-4 lbs N per 1000 sq ft annually; high maintenance due to water and pest needs.
Special Characteristics
Excellent shade tolerance compared to other warm-season grasses; high salt tolerance (good for coastal areas); susceptible to Chinch Bugs and Gray Leaf Spot; poor traffic tolerance compared to Bermuda.
Ecological Information
Introduced/Naturalized in the US; provides soil stabilization in coastal drainage areas; low wildlife value in mowed turf; can be invasive in native coastal sand dunes if escaped.