Charleston, South Carolina, sits in USDA hardiness zone 9a — a band that supports both cool-season staples and warm-season crops chosen to fit the local frost window.
These conditions suit artichoke, fig, california poppy, and cabbage — a starting list any specific site will trim or extend with its own soil, sun, and drainage.
Even in Charleston, 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 Charleston 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 Charleston — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Charleston — the short answer
Charleston, South Carolina: USDA zone 9a, about 320 days between hard freezes, across 74K acres of city.
- USDA zone
- 9a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Feb 1
- Charleston County normal — NOAA 1991–2020, nearest to this town
- First hard freeze (28°F)
- Dec 18
- Charleston County normal — NOAA 1991–2020, nearest to this town
- Days between freezes
- ~320
- Charleston County normal — NOAA 1991–2020, nearest to this town
- City area
- 74K 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 Charleston County’s — the closest measured record, labelled as such rather than passed off as local.
Hardiness Zone Range
Zone 9a is Charleston's average, not your lot's — a low corner or a tree line moves it. Against Charleston's 320-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Charleston
Each reading below is measured for Charleston itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
From county recordsCharleston runs about 320 days between hard freezes (read from Charleston County, the closest normal to Charleston) — 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
MeasuredCharleston 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 Charleston is in
Charleston sits in the Southern Coastal Plain — EPA Level III, inside the wider Eastern Temperate Forests. That is read at Charleston's own centroid rather than borrowed from Charleston County.
What Grows in Charleston
Every plant below cleared Charleston's own zone 9a and its 320-day season. Each card opens that plant's South Carolina profile. How we score.
Is it too late to plant in Charleston?
Usually not — gardeners here simply switch what goes in the ground as the season moves. Cool-season crops can go in from around Jan 4; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Feb 1 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Dec 18 — 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.
Documented around Charleston
Survey cells within 31 miles of Charleston checked for spotted lanternfly, none carrying a detection — a surveyed negative, not an absence of looking. Nearest documented record 155 miles off. What to watch for.
What's on the federal record near Charleston
Closest first, within ~10 miles of Charleston. Listing isn't leaking, and distance isn't exposure.
- RENTAL SERVICE CORP STORE 477Underground Storage Tanks · 0.5 mi
- LANXESS CORPORATION - CHARLESTON, SC PLANTBrownfields · 0.6 mi
- LANXESS CORPORATION - CHARLESTON, SC PLANTToxics Release Inventory · 0.6 mi
- COLUMBIA NITROGENSuperfund · 0.7 mi
- FED SERV, INC.Superfund · 0.8 mi
- EXXONMOBIL OIL CORP 99NCSBrownfields · 0.8 mi
- VIRGINIA CAROLINA CHEMICAL (VCC) WANDOSuperfund · 0.8 mi
- SCE&G HAGOOD STATIONUnderground Storage Tanks · 0.8 mi
- LANXESS CORPORATIONUnderground Storage Tanks · 0.8 mi
- CHN- 108Nitrate · 0.8 mi
- DOLPHIN COVE MARINABrownfields · 0.9 mi
- STONO PHOSPHATE WORKSSuperfund · 0.9 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Charleston'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 Charleston.
Sources Checked
within ~10 miles of Charleston
Severity Distribution
within ~10 miles of Charleston
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Charleston, Superfund runs higher than the national average — 35 sites within ~10 miles of Charleston. 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.
Commission professional soil testing before any food production (test for heavy metals, VOCs, and SVOCs).
Check your specific parcel in Charleston
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 Charleston average
Your land is one point inside Charleston
Everything above resolves to Charleston as a whole — one PHZM band, read across 74K acres, with hard-freeze dates borrowed from Charleston 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 Charleston Average
Charleston Average
- ●USDA Zones 9a, averaged across Charleston
- ●One soil character for all of Charleston
- ●Frost dates read at Charleston's scale: Feb 1 to Dec 18
YOUR Parcel
- ✓Your exact zone, not Charleston's 9a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Charleston
Pull a site-specific report for your exact address in Charleston, South Carolina — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Charleston averages can't show:
We read public map data around Charleston — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Charleston average
How we know this about Charleston
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 Charleston 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 Charleston
When does frost risk typically end in Charleston?
The last hard freeze (28°F) in Charleston typically lands around Feb 1, 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 Feb 22.
When is the first frost in Charleston?
The first hard freeze (28°F) in Charleston typically arrives around Dec 18, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Dec 4, so the watching starts about Nov 18 — about 320 days after the spring freeze cleared.
How long is the growing season in Charleston?
Measured between 28°F hard freezes, Charleston sees about 320 frost-free days — roughly Feb 1 through Dec 18, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Feb 22 to Dec 4, about 285 days.
Is the soil safe to grow vegetables in Charleston?
The federal record around Charleston is a meaningful one — 1,599 documented sites, mostly Underground Storage Tanks entries (908), the nearest Underground Storage Tanks record about 0.5 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 Charleston?
From about Nov 18 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 18 (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 18. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Charleston's scale — its 9a band and its 320-day season. Your yard writes its own version of Charleston'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 Charleston’s own scale
6 of the readings below were taken at Charleston's own scale — the 73,757 acres it covers and 1,599 documented sites around it; 5 are borrowed from a wider read, named and linked below.
Measured here
- Charleston's own USDA hardiness band, zones 9aUSDA PHZM 2023
- 1,599 documented contamination sites on the federal record near Charleston, the closest Underground Storage Tanks record about 0.5 miles out from the town centreFederal environmental registers
- Charleston's boundary and the 73,757 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 9a and a ~320-day seasonGrowable Ground crop-matching engine
- The ecoregion at Charleston's own centroid, the Southern Coastal PlainUS EPA Level III Ecoregions
- Lanternfly survey cells around Charleston checked, none carrying a detectionlydemapr (De Bona & Helmus), 10 km survey lattice
Inherited from a wider read
- The 28°F hard-freeze dates — Charleston has no normal of its own, so its county's is the closest measured readfrom Charleston County
- Soil character — no town-scale survey exists, so Charleston's 73,757 acres read through its county's SSURGO summaryfrom Charleston County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Charleston County
- The growing challenges every South Carolina grower plans around — written at state scale, so they stay on the state guidefrom South Carolina
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Charleston County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Charleston's 73,757 acreswhy one lot differs from the next →
- Which side of Charleston you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 73,757 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record about 0.5 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 Charleston-wide figureread your own land →