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When to plant in Charleston, SC

USDA Zone 9a

Everything below — frost dates, hardiness zone, and what to plant when in Charleston, South Carolina — is derived from the closest NOAA station with complete climate normals.

With about 329 frost-free days, Charleston supports back-to-back plantings; stagger sowings every few weeks to keep beds productive spring through fall. Zone 9a is warm enough that Charleston can grow subtropical perennials, and the short (or absent) frost period barely limits the annual calendar.

Station · CHARLESTON CITY · 6.6 km
Last spring frost
February 4
50% chance · 32°F
First fall frost
December 30
50% chance · 32°F
Growing season
329 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for CharlestonA year-band showing 32°F frost risk from January to December for Charleston: last spring frost around February 4, first fall frost around December 30, about 329 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

The average first fall frost in Charleston is now 6 days later than in the 1981–2010 normals. See how frost dates are shifting nationwide →

Frost probability

CHARLESTON CITY · 1991–2020

The date the last spring and first fall frost occur, by threshold and probability. A 90% date is later in spring — and earlier in fall — than a 10% date; the 50% · 32°F row is what most gardeners plan around. These are Charleston’s own odds, recorded at CHARLESTON CITY.

Frost-probability curves for CharlestonProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around February 4 and the first fall frost around December 30, giving about 329 frost-free days.
Last spring frostFirst fall frostbold = 32°F · thin = 28°F / 36°F · dot = 50% date · band = 10–90% window
ThresholdSPRING 10%SPRING 50%SPRING 90%FALL 10%FALL 50%FALL 90%
36°FMar 17Feb 25Jan 29Nov 20Dec 10Jan 7
32°FMar 4Feb 4Jan 5Dec 2Dec 30Jan 25
28°FFeb 20Jan 24Dec 27Dec 15Jan 8Feb 3

Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.

What to plant now

TODAY · JULY 19

Nothing new to sow or transplant outdoors in the next few weeks — a seasonal lull. Check the full-year calendar below for the next window.

Add the next planting windows to your calendar (.ics) ↓

Full-year planting calendar

Start indoorsTransplantDirect sowFall sow

Each bar is the exact window to take a planting action in Charleston, drawn to the day from the local frost dates. The dashed line is today.

Nearby weather stations

3 within 13 km · complete 32°F normals

When stations disagree by more than a few days, that spread is real microclimate variation — elevation, water, urban heat. Judge which station best matches your own yard.

CHARLESTON CITY
Primary
7 km · 3 m elevation
SPRING
Feb 4
FALL
Dec 30
CHARLESTON INTL AP
10 km · 12 m elevation
SPRING
Mar 7
FALL
Nov 27
SULLIVANS IS
13 km · 2 m elevation
SPRING
Mar 13
FALL
Nov 30

Charleston planting FAQ

When is the last spring frost in Charleston, SC?

On average, the last spring frost in Charleston is around February 4 (50% probability at 32°F, from 1991–2020 NOAA normals). Wait until after this date to set out tender plants like tomatoes and peppers.

When is the first fall frost in Charleston, SC?

The first fall frost in Charleston typically arrives around December 30 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.

What hardiness zone is Charleston in?

Charleston is in USDA hardiness zone 9a. In zone 9a, winters are mild — many tender perennials overwinter here.

How long is the growing season in Charleston?

There are roughly 329 frost-free days in Charleston (a long growing season), running from the average last frost around February 4 to the first fall frost near December 30.

When should I plant tomatoes in Charleston?

In Charleston, start tomato seeds indoors around December 10–December 24, then transplant seedlings outdoors around February 11 once the danger of frost has passed.

Planting reminders

Never miss a window in Charleston

An email when it’s time to start seeds, transplant, and sow — timed to Charleston’s frost dates. Double opt-in, one-click unsubscribe, no spam.

Nearby cities

8 within reach

Frost dates recorded at CHARLESTON CITY, 7 km from the city center · 1991–2020 NOAA climate normals · zone from the USDA/PRISM 2023 map. How we compute this.

Cite this page
BlissGarden. "When to Plant in Charleston, SC — Frost Dates & Zone 9a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USW00013782. Retrieved from https://blissgarden.com/south-carolina/charleston.