St. Augustinegrass vs Zoysiagrass: Which Should You Plant?

St. Augustinegrass is more shade tolerant than zoysia. St. Augustine handles 4 hours of dappled sun and still maintains acceptable density, while zoysia needs at least 4 to 6 hours of direct light. For lawns under mature oak or palm canopy, St. Augustine is the only warm-season grass that consistently performs. Zoysia in similar shade will thin out within 2 to 3 growing seasons.

Zoysiagrass is significantly more cold tolerant than St. Augustinegrass. Zoysia survives winters down to Zone 6 (regular lows in the single digits) and recovers reliably the next spring. St. Augustine begins suffering damage below 25 degrees Fahrenheit and can be killed outright by hard freezes in the 15 to 20 degree range. If you are in Zone 6 or 7, zoysia is the safer pick. St. Augustine is realistically a Zone 8+ grass.

St. Augustinegrass is the better coastal pick because of its high salt tolerance. St. Augustine handles direct salt spray from ocean winds, brackish irrigation water, and storm surge better than any other common warm-season grass. Zoysia has medium salt tolerance and works further inland but struggles within a few hundred feet of the surf. The Floratam, Palmetto, and Seville cultivars of St. Augustine are specifically bred for coastal conditions.

St. Augustinegrass has significantly worse pest pressure than zoysia. Chinch bugs are the primary issue, causing yellow-to-brown patches that can wipe out an entire lawn during summer if untreated. St. Augustine is also more susceptible to gray leaf spot disease, especially in humid Gulf Coast and Florida summers. Zoysia has comparatively low disease and insect pressure, with billbugs being the main pest concern, and they rarely cause whole-lawn damage. Plan on at least one preventive insecticide application per year for St. Augustine in Florida; zoysia often gets by with none.

Zoysia is generally more expensive than St. Augustine. A 500 square foot pallet of zoysia sod runs $300 to $500; St. Augustine runs $200 to $400 for the same coverage. Both are almost always installed as sod (seeding success is poor for both). Over the long run, zoysia costs less to maintain because of lower fertilizer and pest-control needs, but the upfront investment is higher.