St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4
Grass Family
Poaceae, Subfamily Panicoideae, Tribe Paniceae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Common or Floratam-like variety
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 to medium green color. It forms a dense turf that remains low but can reach 6-12 inches if left unmowed. Seed heads are spike-like racemes with seeds embedded in a thick, flattened rachis.
Blade Characteristics
Coarse blades (>4mm width), flat shape with a distinct rounded/obtuse boat-shaped tip. Vernation is folded in the bud. Ligule is a fringe of short hairs; auricles are absent. Distinctive compressed, keeled sheaths.
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 but poor traffic tolerance.
Growing Information
Origin Region
Native to the coastal regions of the Gulf of Mexico, Caribbean, and Mediterranean; adapted to tropical and subtropical climates.
Growth Habit
Stoloniferous; spreads aggressively via above-ground runners (stolons) to form a thick, deep-carpeted mat.
Sunlight & Water Needs
Full Sun to Partial Shade (highly shade tolerant for a warm-season grass); requires 4-6 hours of sun; moderate to high water needs; prefers moist, well-drained soils with pH 5.0-8.5.
Mowing & Maintenance
Mowing height 2.5–4.0 inches; frequency every 5-7 days during peak growth; 2-4 lbs Nitrogen per 1000 sq ft/year; high maintenance level due to water and pest needs.
Special Characteristics
Excellent shade tolerance compared to other warm-season grasses; high salt tolerance; poor foot traffic tolerance; susceptible to Chinch bugs and Gray Leaf Spot.
Ecological Information
Native to coastal areas; provides soil stabilization in sandy regions; non-invasive in most managed landscapes but can crowd out native flora in coastal wetlands if escaped.