Generally — Most Areas
St. Augustine grass (zones 8-10) suits most of Alabama (7b-9b) — zones 8-9 are in range, and the rest of the state is the exception.
St Augustine Grass in Alabama — the short answer
St Augustine Grass in Alabama: hardy in zones 8–10, part sun.
- Plant zones
- 8-10
- Not verified — NC State Extension Gardener Plant Toolbox lists zones 7a–12b
- Alabama zones
- 7b-9b
- USDA PHZM 2023
- Frost window
- Feb 24 - Mar 16 – Nov 15 - Nov 28
- NOAA RCC ACIS 1991-2020, 28°F
- Shortest county season
- 225 days
- NOAA Regional Climate Centers ACIS, 1991-2020, county 28°F killing freeze
Plant data: Growable Ground Plant Database, compiled from FAO ECOCROP, USDA PLANTS and university Extension sources — per-field provenance varies and is published with the dataset.
Your yard isn't the whole zone.
Alabama spans zones 7b-9b, but your yard sits in exactly one — and slope, tree cover, and cold-air pockets nudge it further. Enter your address and we'll score st augustine grass against your parcel's actual hardiness, soil, and sun.
We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.
No card required · your parcel report in seconds — read in full free for your first 14 days
Alabama is not one climate
Alabama’s winter-low ladder runs across 67 counties, from zone 7.5 in Jackson County to zone 9 in Mobile County. That is 15°F between the two counties’ average coldest night — the difference between st augustine grass overwintering in the ground and coming under cover.
The middle half of 67 counties runs 8–8.5 zones, with a median of 8.5 zones — a 1.5-zone span end to end.
Measured across 67 Alabama counties. USDA PHZM 2023, per county. Quartiles are order statistics — every figure shown is a value a real county recorded, not an interpolation. Your own site sits somewhere inside this range; a parcel report resolves where.
Where in Alabama Fits Best
St Augustine Grass is rated for zones 8–10 — a cold floor USDA puts at 10 to 20°F. Against Alabama’s 67 counties that band holds in 63 of them, and the line runs at Bibb County (zone 8a), the coldest county still inside it.
Inside zones 8–10
63 counties
- Blount County · zone 8a
- Calhoun County · zone 8a
- Chambers County · zone 8a
3 of 63 shown
Below the zone 8 floor
4 counties
- Jackson County · zone 7b
- Lauderdale County · zone 7b
- Marion County · zone 7b
3 of 4 shown
Winter cold is the limit here — the same plant works in a container that comes under cover.
County hardiness zones: USDA Plant Hardiness Zone Map (PHZM) 2023, per county. A zone is a 10°F band of average annual extreme minimum temperature, so the floor above is the band the plant's rating denotes, not a single measured kill point. Slope, shelter and cold-air drainage routinely move a site half a zone either way from its county figure — which is the part only your address resolves.
Even within Alabama's zones 7b-9b, county microclimates differ enough to change what thrives. These counties carry the closest zone match for st augustine grass (USDA PHZM 2023):
Zone Comparison
St Augustine Grass Needs
- USDA Zones: 8-10
- Sun: Part Sun
- Mature size: 1 ft tall
- Drought tolerance: Medium
Alabama Has
- USDA Zones: 7b-9b
- Last Hard Freeze (28°F): Feb 24 - Mar 16
- First Hard Freeze (28°F): Nov 15 - Nov 28
- Annual Rainfall: 50-65 inches
- Common Soils: Red clay, Sandy loam, Alluvial
Plant Zone Range (zones 8-10)
Preferred Soil pH
Plant data: Growable Ground Plant Database, compiled from FAO ECOCROP, USDA PLANTS, and university Extension sources — per-field provenance varies and is published with the dataset. State data: USDA ARS PHZM 2023, NOAA Climate Normals, NRCS SSURGO.
When to Plant St Augustine Grass in Alabama
The frost window
Across Alabama, the last spring hard freeze (28°F) clears between Feb 24 and Mar 16, and the first fall hard freeze lands between Nov 15 and Nov 28 (NOAA Regional Climate Centers ACIS, 1991-2020). Counting from the latest last freeze to the earliest first freeze, that's a 244-day window you can count on — up to 277 days on a mild site in a kind year. That marks the hard freeze, not the last light frost, so tender transplants usually wait another 2-3 weeks.
Winter standing
Alabama runs as cold as USDA zone 7, and no sourced winter-hardiness floor is on record for st augustine grass, so this page does not state whether it overwinters here — and gives no fall establishment date on the strength of a guess. Whether st augustine grass is a permanent planting or a replant-every-spring crop for you turns on your own zone within Alabama; check its hardiness range against that before treating it as long-lived ground.
Timing tuned to sub-state frost dates — Marion County, not the statewide average.
Frost window: NOAA Climate Normals 1991-2020. Plant timing fields: Growable Ground Plant Database — frost-free days from FAO ECOCROP, days to harvest from university Extension production guides, and growing-degree-day and chill-hour minimums that are compilation estimates rather than published figures. Your site's own frost dates can run earlier or later than the state range — a parcel report pins them down.
Soil + Drainage Fit
St Augustine Grass tolerates a wide pH range (pH 5-8.5) — 3.5 units, acid ground through alkaline — so soil acidity is rarely what limits it in Alabama. A soil test is still worth having, but for what else it tells you about this site, not to clear this plant. It will grow across that whole span, but it does best between pH 6 and 7.5 — worth knowing before you decide whether a Alabama soil test result is a problem or just a number. Drainage matters: this plant wants well (dry spells). If your Alabama site is heavier clay or sits in a low spot, a raised bed lifts the roots above wet ground, or work in compost.
Your land, not the state average
SSURGO maps about 14.1% of Alabama as poorly or somewhat-poorly drained, and the class flips parcel to parcel. St Augustine Grass sits mid-range for drought tolerance, so either extreme can cost you — your soil map unit, not the state average, is the real answer.
Check your parcel → Source: USDA NRCS SSURGO.
Plant pH requirements: FAO ECOCROP and USDA PLANTS, with the remaining rows from other published sources or Growable Ground compilation. Drainage: FAO ECOCROP, with the remaining rows from other published sources or Growable Ground compilation. Alabama soil profile from USDA NRCS SSURGO. Site-specific verification: a 30-minute soil test from your local Extension lab.
What Else to Consider for St Augustine Grass in Alabama
Zone compatibility tells you about winter cold survival — but Alabama growers also need to think about:
Heavy clay soils in the Piedmont region
High humidity promotes fungal diseases
Fire ants are a persistent garden pest
Growing st augustine grass here specifically
St Augustine Grass needs sharp drainage and sends medium roots; its growing tissue takes cold to about 30°F (FAO ECOCROP), but in Alabama, about 14.1% of soils are poorly-drained (SSURGO), and standing water is what actually kills it.
Build st augustine grass up on a coarse, free-draining mound so its crown never sit in saturated soil. How to handle it →
What to actually do about these — and the constraints that apply to every Alabama grower, not just st augustine grass — is covered on the Alabama growing guide.
Timing shifts within Alabama
Alabama isn't one climate. In Marion County, the last hard freeze (28°F) holds until about Mar 28 — roughly 26 days later than the recorded state median — so plant st augustine grass to your county's window, not the statewide date.
County last-freeze dates: NOAA Regional Climate Centers ACIS (1991-2020), county 28°F freeze (earlier than the folk 32°F "last frost"). A parcel report resolves your address's own frost dates.
Where in Alabama St Augustine Grass Is Zone-Hardy
St Augustine Grass is rated for USDA zones 8–10. 63 of Alabama’s 67 counties fall inside that band. The coldest that does is Bibb County at zone 8a. 4 counties sit below the plant’s zone 8 floor, where an unprotected plant is relying on snow cover and a mild year. Where you are in Alabama decides this one.
Across those 67 counties Alabama’s winter-low ladder runs from zone 7b in Jackson County to zone 9a in Mobile County — 1.5 USDA zones of spread, which is 15°F between the two counties’ average coldest night of the year. That is why a statewide hardiness answer is where you start and not where you finish.
The planting window moves with it. Marion County holds its last hard freeze (28°F) until about Mar 28, while Mobile County is clear by Feb 9 — 47 days apart. Set st augustine grass out on your county’s date, not the state’s.
County hardiness zones: USDA Plant Hardiness Zone Map (PHZM) 2023, per county. County last-freeze dates: NOAA Regional Climate Centers ACIS (1991-2020), county 28°F killing freeze — earlier than the folk 32°F "last frost". St Augustine Grass’s zone 8–10 band: Not verified — NC State Extension Gardener Plant Toolbox lists zones 7a–12b. A parcel report resolves your address’s own zone and frost dates rather than its county’s.
Alabama Cooperative Extension
For Alabama-specific cultivar recommendations, planting calendars, and pest pressure for st augustine grass, the canonical source is Alabama Cooperative Extension System. Their fact sheets carry the local trial data we can't generalize across 50 states.
Is St Augustine Grass native to Alabama?
The USDA PLANTS Database (accessed 2026-10-19) lists St Augustine Grass as native to the Lower 48 and records it growing in Alabama, but it does not say whether those Alabama plants are native or introduced. Your state's native plant society or Cooperative Extension can tell you whether it is part of the local flora.
State records: USDA PLANTS Database state-distribution data (presence, not state-level nativity), accessed 2026-10-19.
Common Questions About Growing St Augustine Grass in Alabama
When can I plant St Augustine Grass in Alabama?
Alabama's last spring hard freeze (28°F) clears between Feb 24 and Mar 16, and the first fall hard freeze lands between Nov 15 and Nov 28 (NOAA Regional Climate Centers ACIS, 1991-2020). No sourced winter-hardiness floor is on record for St Augustine Grass, so this page does not state whether it overwinters in Alabama and publishes no fall establishment date for it — check its hardiness range against your own zone before treating it as a permanent planting.
What hardiness zone is St Augustine Grass grown in across Alabama?
Alabama spans USDA hardiness zones 7b-9b (USDA ARS PHZM 2023). St Augustine Grass carries a range of zones 8-10, so the overlap zones are where outdoor growing is most reliable.
How many frost-free days does a typical Alabama site have?
A typical Alabama site sees ~266 frost-free days per year (derived from NOAA Regional Climate Centers ACIS, 1991-2020). St Augustine Grass needs 150+ frost-free days, so check whether your local microclimate runs above or below the state average before settling on a planting date. In cooler counties like Marion, the freeze-free season runs shorter than the state average, so verify your own county's window.
Is St Augustine Grass native to Alabama?
The USDA PLANTS Database (accessed 2026-10-19) lists St Augustine Grass as native to the Lower 48 and records it growing in Alabama, but it does not say whether those Alabama plants are native or introduced. Your state's native plant society or Cooperative Extension can tell you whether it is part of the local flora.
How should I amend the soil for St Augustine Grass in Alabama?
St Augustine Grass tolerates pH 5-8.5 and well (dry spells) drainage (FAO ECOCROP). That is a 3.5-unit span, acid ground through alkaline, so pH is rarely what limits this plant on a Alabama site — amend for drainage and organic matter first.
Will St Augustine Grass actually grow on my specific land in Alabama?
State-level zone + climate data is a sketch. A Growable Ground parcel report scores st augustine grass against your address's mapped soil pH, drainage, sun, and frost-date data drawn from USDA SSURGO, NOAA, and PRISM — not state averages.
Check your specific parcel in Alabama
State-level data is a sketch. Your Growable Ground report scores st augustine grass against your land's mapped soil, modelled sun, drainage, and frost data — not zone averages.
Three things about your lot that Alabama st augustine grass averages can't show:
We read public map data around Alabama — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Alabama st augustine grass average
Explore More
Growing guides for st augustine grass
Explore Alabama county by county
Alabama carries 67 counties with their own USDA zone — a sample of the growing pages for st augustine grass there:
Where else st augustine grass grows
St Augustine Grass's zone band crosses state lines — these are the states closest to Alabama in winter climate where it also has a page, plus the far ends of its range. Each one re-answers the question with that state's own record.
More to grow in Alabama
Alabama has a growing page for 1,029 plants — a rotating sample of the rest of the shelf.
Analysis by the Growable Ground research team, grounded in USDA PLANTS, USDA NRCS SSURGO, NOAA Climate Normals (1991-2020), and named Cooperative Extension sources. How we know →
Cite this dataset
Kirchick, M. (2026). Growable Ground Plant Database [Data set]. Zenodo. https://doi.org/10.5281/zenodo.21435643
Licensed CC BY-NC 4.0. DOI 10.5281/zenodo.21435643
Last updated: