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Place guide

Planting zones in Charleston-North Charleston, SC

This metro spans USDA zones 8b to 9a, so there is no single zone for Charleston-North Charleston, SC and anyone who gives you one is rounding. 57% of its ZIP codes are zone 9a; the rest are not.

USDA zones 8b–9a 2 zones across 44 ZIP codes
ZIP codes 44 44 have a NOAA station within range
Weather stations 9 NOAA 1991–2020 normals, across 2,590 sq mi

Your ZIP code

Get the exact answer for your address

Everything above describes Charleston-North Charleston, SC as a whole. Hardiness zones and freeze dates are published per ZIP code, so yours is exact β€” enter it and this page will tell you your zone, which NOAA station it comes from and how far away that station is.

Works for all 40,502 US ZIP codes. Freeze dates need a NOAA station within 100 km; where there is none, the page says so rather than estimating one.

Charleston-North Charleston, SC does not have one planting answer

Its own weather stations disagree about 27 of the 32 crops in this table right now, so any single list would be wrong for part of the metro area. That is not a gap in the data β€” it is what the data says.

Shortest season
237 days
HOLLY HILL 1 SW, SC US (USC00384205)
Longest season
321 days
CHARLESTON CITY, SC US (USW00013782)

84 days of growing season separate those two stations, and both serve ZIP codes in Charleston-North Charleston, SC. The ZIP lookup above answers for one address instead of averaging a place that has no average.

Why the hardiness zone does not settle this

A USDA zone is a winter-minimum statistic. It was never a growing-season one, and it does not behave like one: within a single zone the growing season runs a median 54 days wider at the 10th–90th percentile, and annual growing degree days vary by 2.02Γ—.

The zones also overlap rather than stack β€” 30% of zone 6b freezes before the median zone 6a station. The zone tells you what survives your winter; the station tells you what finishes before your autumn.

The whole dataset behind that β†’

Growing season across Charleston-North Charleston, SC A one-year bar. Every one of the 9 NOAA stations serving this metro area counts March 22 to November 12 as growing season, 235 days. At least one counts February 4 to December 30, 329 days. The same figures are written out below this chart. JFMAMJJASONDMarch 22November 12

All 9 stations agreeAt least one station

Every one of the 9 NOAA stations serving this metro area counts March 22 – November 12 as growing season (235 days). Widening to any single station gives February 4 – December 30 (329 days).

That is a 94-day difference inside one metro area β€” which is why this page gives ranges rather than a single planting date. The ZIP lookup above resolves it to one station.

Which zone you are in depends where you are

Charleston-North Charleston, SC covers 2 hardiness zones. A guide that gives the metro one zone has picked whichever is largest and rounded everyone else into it β€” which is fine for the 57% in zone 9a and wrong for the other 43%. Here is the actual split.

Zone ZIP codes Share  
9a 25 57%
8b 19 43%

Zones are published per ZIP code, so yours is exact even though the metro's is not. The hardiness tool will tell you which one you are in.

Your freeze dates

Last spring freeze February 4 – March 22
First fall freeze November 12 – December 30

Those are the earliest and latest medians among the 9 stations serving this metro β€” not an average, and not one station standing in for the rest. Half of years freeze later than a station's own median.

The spread is the point. Even in a metro that is one hardiness zone throughout, its stations disagree about the last spring freeze. Hardiness zone and frost date measure different things β€” a zone is the average annual coldest night, a freeze date is when the season turns β€” and a place can be uniform in one and varied in the other. Use the tools below with your own ZIP rather than the ends of this range.

Your growing season

NOAA publishes a growing-season length for each station, and across the 9 stations serving Charleston-North Charleston, SC it runs 237–321 days . That figure is published, not computed from the two freeze dates β€” subtracting one from the other gives the wrong answer wherever a season crosses New Year. Mean summer high (June–August) runs 86–91 Β°F , at or above the 90 Β°F point where cool-season crops bolt and tomato and pepper pollen fails β€” so midsummer sowings of lettuce and its relatives are worth holding here. Summer rain over the same months runs 16.0–19.8" across those 8 stations, against the rough inch a week β€” about 13 inches over the same 92 days β€” that a vegetable garden is usually reckoned to want. At the middle station that is covered, so watering in Charleston-North Charleston, SC is for the gaps between storms rather than the whole season. The inches are NOAA's published normals; the inch a week is a rule of thumb, and it takes no account of a 90 Β°F summer afternoon drying the soil faster than a cool one.

When to start seeds in Charleston-North Charleston, SC

Every spring job for 63 crop dates, counted from this metro's own last spring freeze. Each is a range across all 9 stations β€” the earliest and latest that job falls anywhere in the metro β€” because no one station speaks for the whole area.

Crop Job When Offset
Green Onions Start indoors January 4 – December 10 8 weeks before
Peppers Start indoors January 4 – December 10 8 weeks before
Arugula Direct sow January 7 – February 22 4 weeks before
Baby Salad Greens Direct sow January 7 – February 22 4 weeks before
Beets Direct sow January 7 – February 22 4 weeks before
Green Onions Direct sow January 7 – February 22 4 weeks before
Mustard Greens Direct sow January 7 – February 22 4 weeks before
Okra Start indoors January 7 – February 22 4 weeks before
Radishes Direct sow January 7 – February 22 4 weeks before
Turnips Direct sow January 7 – February 22 4 weeks before
Cabbage Set out January 14 – March 1 3 weeks before
Carrots Direct sow January 14 – March 1 3 weeks before
Collards Direct sow January 14 – March 1 3 weeks before
Collards Set out January 14 – March 1 3 weeks before
Cucumbers Start indoors January 14 – March 1 3 weeks before
Green Onions Set out January 14 – March 1 3 weeks before
Kale Direct sow January 14 – March 1 3 weeks before
Kale Set out January 14 – March 1 3 weeks before
Kohlrabi Direct sow January 14 – March 1 3 weeks before
Kohlrabi Set out January 14 – March 1 3 weeks before
Leaf Lettuce Direct sow January 14 – March 1 3 weeks before
Pumpkins Start indoors January 14 – March 1 3 weeks before
Summer Squash Start indoors January 14 – March 1 3 weeks before
Winter Squash Start indoors January 14 – March 1 3 weeks before
Zucchini Start indoors January 14 – March 1 3 weeks before
Broccoli Start indoors January 18 – December 24 6 weeks before
Cabbage Start indoors January 18 – December 24 6 weeks before
Collards Start indoors January 18 – December 24 6 weeks before
Kale Start indoors January 18 – December 24 6 weeks before
Leaf Lettuce Start indoors January 18 – December 24 6 weeks before
Peas Direct sow January 18 – December 24 6 weeks before
Spinach Direct sow January 18 – December 24 6 weeks before
Sweet Potato Start indoors January 18 – December 24 6 weeks before
Tomatoes Start indoors January 18 – December 24 6 weeks before
Bok Choy Direct sow January 21 – March 8 2 weeks before
Bok Choy Set out January 21 – March 8 2 weeks before
Broccoli Set out January 21 – March 8 2 weeks before
Cilantro Direct sow January 21 – March 8 2 weeks before
Leaf Lettuce Set out January 21 – March 8 2 weeks before
Swiss Chard Direct sow January 21 – March 8 2 weeks before
Swiss Chard Set out January 21 – March 8 2 weeks before
Bok Choy Start indoors January 25 – December 31 5 weeks before
Kohlrabi Start indoors January 25 – December 31 5 weeks before
Swiss Chard Start indoors January 25 – December 31 5 weeks before
Dill Direct sow January 28 – March 15 1 week before
Bush Beans Direct sow February 11 – March 29 1 week after
Cucumbers Set out February 11 – March 29 1 week after
Pumpkins Direct sow February 11 – March 29 1 week after
Pumpkins Set out February 11 – March 29 1 week after
Summer Squash Direct sow February 11 – March 29 1 week after
Summer Squash Set out February 11 – March 29 1 week after
Sweet Corn Direct sow February 11 – March 29 1 week after
Tomatoes Set out February 11 – March 29 1 week after
Winter Squash Direct sow February 11 – March 29 1 week after
Winter Squash Set out February 11 – March 29 1 week after
Zucchini Direct sow February 11 – March 29 1 week after
Zucchini Set out February 11 – March 29 1 week after
Cucumbers Direct sow February 18 – April 5 2 weeks after
Okra Direct sow February 18 – April 5 2 weeks after
Okra Set out February 18 – April 5 2 weeks after
Peppers Set out February 18 – April 5 2 weeks after
Southern Peas Direct sow February 18 – April 5 2 weeks after
Sweet Potato Set out February 18 – April 5 2 weeks after

The week offsets are conventional extension guidance and vary by variety; the freeze dates they are counted from are measured. For a single date rather than a range, run when do I start my seeds? with your own ZIP code.

What survives the winter changes across Charleston-North Charleston, SC

Of 74 perennial fruits, nuts, berries, vegetables and herbs, 54 come through the winter in zone 8b and only 46 in zone 9a. That is a different garden at each end of the same metro.

Zone ZIPs Survive Fail for being too warm
8b 19 54 of 74 11
9a 25 46 of 74 25

The last column is the counterintuitive one, and it is why the totals do not simply rise as the winters get milder. Most temperate fruit needs a documented number of hours below about 45 Β°F to break dormancy and set a crop, so an apple fails in a winter that is too warm; currants and rhubarb cook in the summer heat that comes with it. See the full list with reasons.

At least one station here freezes across the new year, which puts the two ends of a spread on opposite sides of the calendar. Drawing it would produce a bar spanning almost the whole year and meaning nothing, so none is drawn.

The 9 stations behind these numbers

The 9 NOAA stations serving Charleston-North Charleston, SC A relative sketch of where the stations sit, about 79 kilometres north to south. Each is named with its NOAA identifier in the station list on this page, which carries the same information as text. CHARLESTON CITY, SC US (USW00013782)CHARLESTON INTL AP, SC US (USW00013880)EDISTO IS MIDDLETON PLANTATION, SC US (USC00382735)HOLLY HILL 1 SW, SC US (USC00384205)JAMESTOWN, SC US (USC00384449)MCCLELLANVILLE, SC US (USC00385628)MONCKS CORNER 4 N, SC US (USC00385946)SULLIVANS IS, SC US (USC00388405)SUMMERVILLE 4W, SC US (USC00388426) ~79 km north to south

All 9 NOAA stations whose normals this page quotes, spanning about 79 km north to south. Every one is named with its identifier in the station list below β€” this page does not single one out, because no one station speaks for a whole metro area.

A relative sketch, not a map with a projection: longitude is adjusted for latitude so the shape is not stretched, and there is no basemap. For the one station nearest a specific address, with its real distance, use the ZIP lookup above.

Every figure above comes from these, and each is named so you can check it. Which station serves a given ZIP code, and how far away it is, varies across the metro β€” the table below gives it per ZIP code rather than this page averaging it.

Station NOAA ID Last spring freeze First fall freeze Season
Charleston City, SC USW00013782 February 4 December 30 321 days
Charleston INTL AP, SC USW00013880 March 7 November 27 266 days
Edisto Is Middleton Plantation, SC USC00382735 March 1 December 6 284 days
Holly Hill 1 SW, SC USC00384205 March 22 November 12 237 days
Jamestown, SC USC00384449 March 22 November 13 238 days
Mcclellanville, SC USC00385628 March 17 November 21 250 days
Moncks Corner 4 N, SC USC00385946 March 10 November 26 265 days
Sullivans Is, SC USC00388405 March 13 November 30 262 days
Summerville 4W, SC USC00388426 March 22 November 12 238 days

These are medians, not averages β€” NOAA publishes freeze dates as a probability distribution, and half of years freeze later than the date shown.

Every ZIP code in Charleston-North Charleston, SC

Zones are published per ZIP code, not per metro area, so this is the exact answer rather than the metro area's average. The station column is the nearest one to that ZIP code's centroid and how far away it is β€” the same figure the tools use, shown here so you can see which ZIP codes are well covered and which are reaching.

ZIP code USDA zone Nearest NOAA station Distance
29401 9a Charleston City, SC 0.3 km
29403 9a Charleston City, SC 2.9 km
29404 9a Charleston INTL AP, SC 1.1 km
29405 9a Charleston INTL AP, SC 7.6 km
29406 9a Charleston INTL AP, SC 4.3 km
29407 9a Charleston City, SC 6.5 km
29410 9a Charleston INTL AP, SC 5.0 km
29412 9a Charleston City, SC 7.8 km
29414 9a Charleston INTL AP, SC 8.6 km
29418 9a Charleston INTL AP, SC 5.3 km
29420 9a Charleston INTL AP, SC 6.7 km
29426 9a Edisto Is Middleton Plantation, SC 18.9 km
29429 9a Mcclellanville, SC 23.1 km
29431 8b Moncks Corner 4 N, SC 10.3 km
29434 8b Moncks Corner 4 N, SC 17.5 km
29436 8b Moncks Corner 4 N, SC 20.3 km
29437 8b Holly Hill 1 SW, SC 20.2 km
29438 9a Edisto Is Middleton Plantation, SC 4.6 km
29439 9a Charleston City, SC 14.9 km
29445 8b Charleston INTL AP, SC 12.9 km
29448 8b Holly Hill 1 SW, SC 7.6 km
29449 9a Edisto Is Middleton Plantation, SC 11.1 km
29450 8b Jamestown, SC 23.0 km
29451 9a Sullivans Is, SC 12.4 km
29453 8b Jamestown, SC 10.7 km
29455 9a Charleston City, SC 18.4 km
29456 8b Charleston INTL AP, SC 11.7 km
29458 9a Mcclellanville, SC 6.1 km
29461 8b Moncks Corner 4 N, SC 8.2 km
29464 9a Sullivans Is, SC 6.4 km
29466 9a Sullivans Is, SC 14.4 km
29468 8b Moncks Corner 4 N, SC 22.3 km
29469 8b Moncks Corner 4 N, SC 13.4 km
29470 9a Charleston INTL AP, SC 18.4 km
29471 8b Holly Hill 1 SW, SC 27.2 km
29472 8b Summerville 4W, SC 8.9 km
29477 8b Holly Hill 1 SW, SC 21.9 km
29479 8b Moncks Corner 4 N, SC 17.8 km
29482 9a Sullivans Is, SC 2.6 km
29483 8b Summerville 4W, SC 0.7 km
29485 8b Summerville 4W, SC 11.7 km
29486 8b Summerville 4W, SC 9.6 km
29487 9a Edisto Is Middleton Plantation, SC 14.4 km
29492 9a Charleston INTL AP, SC 15.2 km

ZIP-code positions are area centroids, so a large rural ZIP code's listed distance is measured from the middle of its area rather than from any particular address in it.

Your own ZIP

Work out your own dates

Each of these takes a ZIP code and answers for that ZIP alone, citing the station it used and how far away it is. There is a ZIP box in the header of every page.

Other places to compare

These metros span exactly the same zones β€” 8b–9a β€” so the same plants are in and out of range across them. The freeze dates and the spring calendar are their own.

Gardening in South Carolina β€” zones 8a– 9b covers the whole state: how its 418 ZIP codes divide between 4 hardiness zones, and the freeze dates across every NOAA station in it.

Other metro areas in SC:

All 388 metro areas, by state

Gear

If you want to act on this

Each link opens an Amazon search rather than a product we picked. We have not tested these and do not rank them β€” the search is the honest version, and you choose.

As an Amazon Associate we earn from qualifying purchases. That costs you nothing extra, and it buys no influence over anything on this site: the dates come from NOAA normals and the zones from the USDA, and no product affects either.

Sources

Where these numbers come from

The hardiness zone is the USDA 2023 Plant Hardiness Zone Map, published per ZIP code by PRISM at Oregon State. The freeze dates are NOAA's 1991–2020 Climate Normals, read from every station whose normals cover a ZIP code in this metro. Nothing here is estimated, and no station stands in for another.

This page names no single station on purpose. Picking one to represent a metro sounds reasonable and is not: the station serving the most ZIP codes is an artifact of where ZIP centroids happen to fall, and it selects a lock on the Monongahela for Pittsburgh and a far southern suburb for Chicago. A range across every station is true; a single cited date for a whole metro is not.

All metro areas