Wilmington Island, Georgia, sits in USDA hardiness zone 9a — a range where zone-matched perennials and frost-aware annual timing set what succeeds.
Growers here do well with artichoke, fig, california poppy, and cabbage — with the usual caveat that any single yard's soil, sun, and drainage cast the deciding vote.
Even in Wilmington Island, 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 Wilmington Island 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 Wilmington Island — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Wilmington Island — the short answer
Wilmington Island, Georgia: USDA zone 9a, about 304 days between hard freezes, across 5K acres of town.
- USDA zone
- 9a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Feb 8
- Chatham County normal — NOAA 1991–2020, nearest to this town
- First hard freeze (28°F)
- Dec 9
- Chatham County normal — NOAA 1991–2020, nearest to this town
- Days between freezes
- ~304
- Chatham County normal — NOAA 1991–2020, nearest to this town
- Town area
- 5K 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 Chatham County’s — the closest measured record, labelled as such rather than passed off as local.
Hardiness Zone Range
Zone 9a is Wilmington Island's average, not your lot's — a low corner or a tree line moves it. Against Wilmington Island's 304-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Wilmington Island
Each reading below is measured for Wilmington Island itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
From county recordsWilmington Island runs about 304 days between hard freezes (read from Chatham County, the closest normal to Wilmington Island) — 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
MeasuredWilmington Island sits in USDA hardiness zone 9a.
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 Wilmington Island is in
Wilmington Island sits in the Southern Coastal Plain — EPA Level III, inside the wider Eastern Temperate Forests. That is read at Wilmington Island's own centroid rather than borrowed from Chatham County.
What Grows in Wilmington Island
Every plant below cleared Wilmington Island's own zone 9a and its 304-day season. Each card opens that plant's Georgia profile. How we score.
Is it too late to plant in Wilmington Island?
Rarely: the season closes in stages, not all at once, and each stage has its crops. Cool-season crops can go in from around Jan 11; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Feb 8 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Dec 9 — long-season crops need about 90 days of runway, quick greens only 30. And with a calendar this mild, the honest answer is that planting barely stops — winter opens seasons colder regions never see.
What's on the federal record near Wilmington Island
Closest first, within ~10 miles of Wilmington Island. Listing isn't leaking, and distance isn't exposure.
- PUMP STATION 39/WILMINGTON PARKUnderground Storage Tanks · 0.7 mi
- MISS JUDYS CHARTERSUnderground Storage Tanks · 0.9 mi
- GA DNRUnderground Storage Tanks · 0.9 mi
- LIFT STATION 38Underground Storage Tanks · 1.0 mi
- BST/WILMINGTON ISL CO/R2212Underground Storage Tanks · 1.0 mi
- LIL CHAMP/HUNTLEY JIFFY STORE #3Underground Storage Tanks · 1.1 mi
- SAVANNAH BEE COMPANYBrownfields · 1.1 mi
- HOGAN'S MARINAUnderground Storage Tanks · 1.1 mi
- CIRCLE K #2705159Underground Storage Tanks · 1.1 mi
- ENK846Underground Storage Tanks · 1.1 mi
- JOHN'S CHEVRONUnderground Storage Tanks · 1.1 mi
- AUTOPLEXUnderground Storage Tanks · 1.2 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Wilmington Island'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 Wilmington Island.
Total Sites
679
within ~10 miles of Wilmington Island
Risk Level
Elevated
Highest-severity
9 Superfund sites (none NPL-listed)
Sources Checked
within ~10 miles of Wilmington Island
Severity Distribution
within ~10 miles of Wilmington Island
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Wilmington Island, two things run higher than the national average within ~10 miles of Wilmington Island — PFAS (7 sites) and Underground Storage Tanks (458 sites). Knowing it is half the work — and it's nothing a thoughtful grower can't plan for.
PFAS: PFAS (per- and polyfluoroalkyl substances) are called "forever chemicals" because they do not biodegrade.
Underground Storage Tanks: Underground storage tanks are the single most common source of soil contamination near homes and gardens.
Test irrigation water source — this is the primary pathway for PFAS to reach garden crops.
Use raised beds with imported soil — this eliminates the primary soil-contact pathway.
Check your specific parcel in Wilmington Island
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 Wilmington Island average
Your land is one point inside Wilmington Island
Everything above resolves to Wilmington Island as a whole — one PHZM band, read across 5K acres, with hard-freeze dates borrowed from Chatham County’s record because no 30-year normal resolves at this town’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 town 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 Wilmington Island Average
Wilmington Island Average
- ●USDA Zones 9a, averaged across Wilmington Island
- ●One soil character for all of Wilmington Island
- ●Frost dates read at Wilmington Island's scale: Feb 8 to Dec 9
YOUR Parcel
- ✓Your exact zone, not Wilmington Island's 9a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Wilmington Island
Pull a site-specific report for your exact address in Wilmington Island, Georgia — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Wilmington Island averages can't show:
We read public map data around Wilmington Island — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Wilmington Island average
How we know this about Wilmington Island
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read at this town’s own centroid; hard-freeze dates from NOAA 1991–2020 28°F normals at Chatham 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 town grain anywhere on this page — there is no town-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 Wilmington Island
When does frost risk typically end in Wilmington Island?
The last hard freeze (28°F) in Wilmington Island typically lands around Feb 8, 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 1.
When is the first frost in Wilmington Island?
The first hard freeze (28°F) in Wilmington Island typically arrives around Dec 9, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Nov 25, so the watching starts about Nov 9 — about 304 days after the spring freeze cleared.
How long is the growing season in Wilmington Island?
Measured between 28°F hard freezes, Wilmington Island sees about 304 frost-free days — roughly Feb 8 through Dec 9, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Mar 1 to Nov 25, about 269 days.
Is the soil safe to grow vegetables in Wilmington Island?
The federal record around Wilmington Island is a meaningful one — 679 documented sites, mostly Underground Storage Tanks entries (458), the nearest Underground Storage Tanks record about 0.7 miles 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 Wilmington Island?
From about Nov 9 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 Dec 9 (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 Dec 9. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Wilmington Island's scale — its 9a band and its 304-day season. Your yard writes its own version of Wilmington Island'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 Wilmington Island’s own scale
5 of the readings below were taken at Wilmington Island's own scale — the 5,313 acres it covers and 679 documented sites around it; 5 are borrowed from a wider read, named and linked below.
Measured here
- Wilmington Island's own USDA hardiness band, zones 9aUSDA PHZM 2023
- 679 documented contamination sites on the federal record near Wilmington Island, the closest Underground Storage Tanks record about 0.7 miles out from the town centreFederal environmental registers
- Wilmington Island's boundary and the 5,313 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 9a and a ~304-day seasonGrowable Ground crop-matching engine
- The ecoregion at Wilmington Island's own centroid, the Southern Coastal PlainUS EPA Level III Ecoregions
Inherited from a wider read
- The 28°F hard-freeze dates — Wilmington Island has no normal of its own, so its county's is the closest measured readfrom Chatham County
- Soil character — no town-scale survey exists, so Wilmington Island's 5,313 acres read through its county's SSURGO summaryfrom Chatham County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Chatham 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 Chatham County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Wilmington Island's 5,313 acreswhy one lot differs from the next →
- Which side of Wilmington Island you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 5,313 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record about 0.7 miles 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 Wilmington Island-wide figureread your own land →
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