Whitemarsh Island, Georgia, sits in USDA hardiness zone 9a — a zone band wide enough that plant choice, not possibility, is the interesting question.
On paper, artichoke, fig, california poppy, and cabbage all suit these conditions — on the ground, soil, sun, and drainage make the final call.
Even in Whitemarsh 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 Whitemarsh 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 Whitemarsh Island — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Whitemarsh Island — the short answer
Whitemarsh Island, Georgia: USDA zone 9a, about 304 days between hard freezes, across 4K 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
- 4K 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 Whitemarsh Island's average, not your lot's — a low corner or a tree line moves it. Against Whitemarsh 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 Whitemarsh Island
Each reading below is measured for Whitemarsh Island itself — here is what it means for a garden here, and the move an experienced grower makes about it.

Season length
From county recordsWhitemarsh Island runs about 304 days between hard freezes (read from Chatham County, the closest normal to Whitemarsh 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
MeasuredWhitemarsh 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 Whitemarsh Island is in
Whitemarsh Island sits in the Southern Coastal Plain — EPA Level III, inside the wider Eastern Temperate Forests. That is read at Whitemarsh Island's own centroid rather than borrowed from Chatham County.
What Grows in Whitemarsh Island
Every plant below cleared Whitemarsh 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 Whitemarsh Island?
Too late for some crops, right on time for others — a growing season is a sequence, not a deadline. 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. Here the calendar nearly circles: cool-season crops take the winter shift, and the next window is always close.
What's on the federal record near Whitemarsh Island
Closest first, within ~10 miles of Whitemarsh Island. Listing isn't leaking, and distance isn't exposure.
- SAFFOLD AIR FIELDUnderground Storage Tanks · 0.6 mi
- SAVANNAH YACHT CLUBUnderground Storage Tanks · 0.7 mi
- PUBLIX SUPERMARKET 521 ISLAND TOWNE CENTERBrownfields · 0.9 mi
- OATLAND ISLAND EDUCATION CENTERSuperfund · 1.6 mi
- SAVANNAH-WILMINGTON ISLANDPFAS · 1.8 mi
- SAVANNAH-WHITEMARSH ISLANDPFAS · 1.8 mi
- WALGREENS #6098Brownfields · 1.8 mi
- CVS PHARMACY #4230Brownfields · 1.8 mi
- PUBLIX SUPERMARKET 456 PUBLIX AT WILMINGTON ISLANDBrownfields · 1.8 mi
- SAVE ON GAS #6Underground Storage Tanks · 1.9 mi
- ENK660Underground Storage Tanks · 1.9 mi
- AUTOPLEXUnderground Storage Tanks · 1.9 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Whitemarsh 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 Whitemarsh Island.
Total Sites
926
within ~10 miles of Whitemarsh Island
Risk Level
Elevated
Highest-severity
14 Superfund sites (none NPL-listed)
Sources Checked
within ~10 miles of Whitemarsh Island
Severity Distribution
within ~10 miles of Whitemarsh Island
Highest-Severity Sites

A note from Gnorman
What an experienced grower watches for around here
In and around Whitemarsh Island, two things run higher than the national average within ~10 miles of Whitemarsh Island — Superfund (14 sites) and PFAS (9 sites). Knowing it is half the work — and it's nothing a thoughtful grower can't plan for.
Superfund: Superfund sites represent the most severe contamination in the federal system.
PFAS: PFAS (per- and polyfluoroalkyl substances) are called "forever chemicals" because they do not biodegrade.
Commission professional soil testing before any food production (test for heavy metals, VOCs, and SVOCs).
Test irrigation water source — this is the primary pathway for PFAS to reach garden crops.
Check your specific parcel in Whitemarsh 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 Whitemarsh Island average
Your land is one point inside Whitemarsh Island
Everything above resolves to Whitemarsh Island as a whole — one PHZM band, read across 4K 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 Whitemarsh Island Average
Whitemarsh Island Average
- ●USDA Zones 9a, averaged across Whitemarsh Island
- ●One soil character for all of Whitemarsh Island
- ●Frost dates read at Whitemarsh Island's scale: Feb 8 to Dec 9
YOUR Parcel
- ✓Your exact zone, not Whitemarsh Island's 9a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Whitemarsh Island
Pull a site-specific report for your exact address in Whitemarsh Island, Georgia — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Whitemarsh Island averages can't show:
We read public map data around Whitemarsh Island — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Whitemarsh Island average
How we know this about Whitemarsh 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 Whitemarsh Island
When does frost risk typically end in Whitemarsh Island?
The last hard freeze (28°F) in Whitemarsh 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 Whitemarsh Island?
The first hard freeze (28°F) in Whitemarsh 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 Whitemarsh Island?
Measured between 28°F hard freezes, Whitemarsh 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 Whitemarsh Island?
The federal record around Whitemarsh Island is a meaningful one — 926 documented sites, mostly Underground Storage Tanks entries (615), the nearest Underground Storage Tanks record about 0.6 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 Whitemarsh 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 Whitemarsh Island's scale — its 9a band and its 304-day season. Your yard writes its own version of Whitemarsh 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 Whitemarsh Island’s own scale
5 of the readings below were taken at Whitemarsh Island's own scale — the 3,722 acres it covers and 926 documented sites around it; 5 are borrowed from a wider read, named and linked below.
Measured here
- Whitemarsh Island's own USDA hardiness band, zones 9aUSDA PHZM 2023
- 926 documented contamination sites on the federal record near Whitemarsh Island, the closest Underground Storage Tanks record about 0.6 miles out from the town centreFederal environmental registers
- Whitemarsh Island's boundary and the 3,722 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 Whitemarsh Island's own centroid, the Southern Coastal PlainUS EPA Level III Ecoregions
Inherited from a wider read
- The 28°F hard-freeze dates — Whitemarsh 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 Whitemarsh Island's 3,722 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 Whitemarsh Island's 3,722 acreswhy one lot differs from the next →
- Which side of Whitemarsh 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 3,722 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record about 0.6 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 Whitemarsh Island-wide figureread your own land →
More in Georgia
Growing region
Nearby growing guides
