Irwinton, Georgia, sits in USDA hardiness zone 8b — a band that supports both cool-season staples and warm-season crops chosen to fit the local frost window.
Reliable performers under these conditions include cabbage, fig, california poppy, and collard greens; what your own ground favors still comes down to its soil, sun, and drainage.
Even in Irwinton, no two yards are alike.
A low spot, a south-facing slope, or a stand of trees moves the frost date and sun across a single Irwinton lot. Enter your address and we'll score 1,086 plants against your land's actual soil, sun, and frost.
We read public map data around Irwinton — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Irwinton — the short answer
Irwinton, Georgia: USDA zone 8b, about 270 days between hard freezes, across 2K acres of city.
- USDA zone
- 8b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Mar 2
- Wilkinson County normal — NOAA 1991–2020, nearest to this town
- First hard freeze (28°F)
- Nov 27
- Wilkinson County normal — NOAA 1991–2020, nearest to this town
- Days between freezes
- ~270
- Wilkinson County normal — NOAA 1991–2020, nearest to this town
- City area
- 2K acres
- US Census TIGER/Line 2025
Every figure names the dataset it came from. No 30-year normal resolves at this town’s own centroid, so the hard-freeze dates are Wilkinson County’s — the closest measured record, labelled as such rather than passed off as local.
Hardiness Zone Range
Zone 8b is Irwinton's average, not your lot's — a low corner or a tree line moves it. Against Irwinton's 270-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Irwinton
Each reading below is measured for Irwinton itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
From county recordsIrwinton runs about 270 days between hard freezes (read from Wilkinson County, the closest normal to Irwinton) — close to year-round growing.
Frost is rarely the limit here; winter plantings are as real as summer ones, and the harder question is which crops shrug off the summer heat.
Grow cool-season crops through the mild winter, and choose heat-tolerant varieties for the summer beds.
NOAA 1991–2020 Climate Normals
Winter hardiness
MeasuredIrwinton sits in USDA hardiness zone 8b.
The zone sets which perennials, shrubs, and fruit trees live through an average winter here — a plant rated for a colder zone is a safe bet, one rated warmer needs winter protection or gets treated as an annual.
Match perennials and fruit to the zone before you buy, so nothing you plant is a gamble against the cold.
USDA PHZM 2023
The kind of country Irwinton is in
Irwinton sits in the Southeastern Plains — EPA Level III, inside the wider Eastern Temperate Forests. That is read at Irwinton's own centroid rather than borrowed from Wilkinson County.
What Grows in Irwinton
Every plant below cleared Irwinton's own zone 8b and its 270-day season. Each card opens that plant's Georgia profile. How we score.
Is it too late to plant in Irwinton?
Almost never — the real question is what to plant next. Cool-season crops can go in from around Feb 2; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 2 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 27 — long-season crops need about 90 days of runway, quick greens only 30. In a climate this gentle, “too late” hardly applies — the question becomes which crops prefer the cooler months ahead.
What's on the federal record near Irwinton
Closest first, within ~10 miles of Irwinton. Listing isn't leaking, and distance isn't exposure.
- LOYD OIL CO(OLD STATION)Underground Storage Tanks · 450 ft
- 20W006Nitrate · 550 ft
- PHILLIPS 66 SERVICE STATIONUnderground Storage Tanks · 600 ft
- JET #46Underground Storage Tanks · 1000 ft
- GA DOT #10240 WILKINSON CO MAINTUnderground Storage Tanks · 1100 ft
- CHAMBERS STANDARD SERV STATIONUnderground Storage Tanks · 0.6 mi
- ROAD DEPTUnderground Storage Tanks · 0.6 mi
- 20W043Nitrate · 0.6 mi
- 20W044Nitrate · 0.8 mi
- ACCUCOMMUnderground Storage Tanks · 0.9 mi
- J M HUBER/WILKINSON COUnderground Storage Tanks · 1.4 mi
- LOYD OILUnderground Storage Tanks · 1.6 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Irwinton's center, not your beds. Run your own address for what's upwind of you specifically.
Environmental Intelligence
The counts behind that headline — every source type on the record near Irwinton.
Total Sites
99
within ~10 miles of Irwinton
Risk Level
Elevated
Highest-severity
1 Superfund site (none NPL-listed)
Sources Checked
within ~10 miles of Irwinton
Severity Distribution
within ~10 miles of Irwinton
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Irwinton, two things run higher than the national average within ~10 miles of Irwinton — Nitrate (40 sites) and Toxics Release Inventory (7 sites). It's not cause for alarm — it's worth knowing, and there's a sensible way to grow around it.
Nitrate: Nitrate contamination primarily comes from agricultural fertilizer runoff and failing septic systems.
Toxics Release Inventory: TRI facilities report annual chemical releases to air, water, and land.
Test well water for nitrate if you rely on a private well for irrigation (EPA standard: 10 mg/L).
Check prevailing wind direction — downwind parcels face higher exposure than upwind or crosswind locations.
Check your specific parcel in Irwinton
Get exact proximity distances to contamination sources for your specific parcel — plus soil, sun, drainage, and 1,086 plant recommendations.
25+ data sources read at your address, not the Irwinton average
Your land is one point inside Irwinton
Everything above resolves to Irwinton as a whole — one PHZM band, read across 2K acres, with hard-freeze dates borrowed from Wilkinson County’s record because no 30-year normal resolves at this city’s own centroid. Your parcel is one point inside that footprint. Slope, tree cover, a low spot that pools cold air, and what is in the soil are all resolved at the address, and none of them are visible at city scale. That is the honest boundary of this page, and the reason the next step is a reading of your own ground rather than a better local average.
Your Lot vs the Irwinton Average
Irwinton Average
- ●USDA Zones 8b, averaged across Irwinton
- ●One soil character for all of Irwinton
- ●Frost dates read at Irwinton's scale: Mar 2 to Nov 27
YOUR Parcel
- ✓Your exact zone, not Irwinton's 8b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Irwinton
Pull a site-specific report for your exact address in Irwinton, Georgia — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Irwinton averages can't show:
We read public map data around Irwinton — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Irwinton average
How we know this about Irwinton
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read at this city’s own centroid; hard-freeze dates from NOAA 1991–2020 28°F normals at Wilkinson County’s record, because none resolves here; boundaries and acreage from US Census TIGER/Line 2025; the contamination records from the federal sources named in their beats above. Soil is not read at city grain anywhere on this page — there is no city-resolution survey in our data, which is why you will find no soil grid here rather than a statewide one wearing a local label. The resolution ledger below names every figure this page inherited.
Common questions about Irwinton
When does frost risk typically end in Irwinton?
The last hard freeze (28°F) in Irwinton typically lands around Mar 2, per NOAA 1991–2020 climate normals — earlier than the light-frost dates most charts quote. That marks the hard freeze, not the last light frost — lighter frosts keep biting past it, which is why tender transplants here wait until about Mar 23.
When is the first frost in Irwinton?
The first hard freeze (28°F) in Irwinton typically arrives around Nov 27, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Nov 13, so the watching starts about Oct 28 — about 270 days after the spring freeze cleared.
How long is the growing season in Irwinton?
Measured between 28°F hard freezes, Irwinton sees about 270 frost-free days — roughly Mar 2 through Nov 27, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Mar 23 to Nov 13, about 235 days.
Is the soil safe to grow vegetables in Irwinton?
The federal record around Irwinton is a meaningful one — 99 documented sites, mostly Underground Storage Tanks entries (44), the nearest Underground Storage Tanks record under a tenth of a mile out — so a soil test before new food beds is a sensible precaution here, not a reason to hold back from growing. Remember that proximity to a documented site is information, not a diagnosis of any one yard; the contamination map shows exactly what sits where.
How do I protect my plants from frost in Irwinton?
From about Oct 28 the job here turns from planting to protecting — the last start even a 30-day crop can finish. As the season closes around the first 28°F hard freeze near Nov 27 (NOAA 1991–2020 climate normals), three moves buy time: row cover or an old sheet over tender plants on still, clear nights; water the soil the afternoon before a freeze, so it holds warmth overnight; and harvest tomatoes, peppers and basil before Nov 27. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Irwinton's scale — its 8b band and its 270-day season. Your yard writes its own version of Irwinton's numbers: we read soil, sun, drainage and frost at your exact address. Try it for 14 days — no card required.
What this page reads at Irwinton’s own scale
5 of the readings below were taken at Irwinton's own scale — the 2,013 acres it covers and 99 documented sites around it; 5 are borrowed from a wider read, named and linked below.
Measured here
- Irwinton's own USDA hardiness band, zones 8bUSDA PHZM 2023
- 99 documented contamination sites on the federal record near Irwinton, the closest Underground Storage Tanks record under a tenth of a mile out from the town centreFederal environmental registers
- Irwinton's boundary and the 2,013 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 8b and a ~270-day seasonGrowable Ground crop-matching engine
- The ecoregion at Irwinton's own centroid, the Southeastern PlainsUS EPA Level III Ecoregions
Inherited from a wider read
- The 28°F hard-freeze dates — Irwinton has no normal of its own, so its county's is the closest measured readfrom Wilkinson County
- Soil character — no town-scale survey exists, so Irwinton's 2,013 acres read through its county's SSURGO summaryfrom Wilkinson County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Wilkinson County
- The growing challenges every Georgia grower plans around — written at state scale, so they stay on the state guidefrom Georgia
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Wilkinson County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Irwinton's 2,013 acreswhy one lot differs from the next →
- Which side of Irwinton you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 2,013 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record under a tenth of a mile out, measured from the town centrehow we read the record →
- Where cold air settles, which slopes face the sun, and which way the wind runs on your own ground — measured at your address, and averaged away by any Irwinton-wide figureread your own land →
More in Georgia
Wider growing context
What grows across GeorgiaIrwinton sits outside our named growing regions, so Georgia as a whole is its closest context here.