When to Plant Cucumbers in South Carolina: Spring and Fall Dates, Coastal and Piedmont

Planting dates for cucumbers from Clemson Cooperative Extension in South Carolina, with 50% frost dates from NOAA for Charleston International Airport, Columbia Owens Downtown Airport, and Greenville Downtown Airport and one worked case.

By Paul Gunder · How we check our sources

Updated November 11, 2026

Figures checked against their sources on November 11, 2026; next check May 8, 2027.

The cucumber entry under the heading “Cucumber” in South Carolina’s calendar is read across 2 regions. Reading down the first date column, Coastal leads at March 15 and Piedmont trails at April 15. A reader has to infer from the packet whether these dates are for seed or for transplants, since the row does not say.

The cucumber windows by region

In Clemson’s spacing table the same crop is listed at 50-60 days to harvest, 60 x 12 inches between rows and plants.

Cucumber planting dates in South Carolina, as printed by Clemson Cooperative Extension (one row per region, none averaged)
Region	Spring planting	Fall planting
Coastal	Mar 15 to May 15	Aug 1 to Aug 30
Piedmont	Apr 15 to Jun 5	Aug 1 to Sept 30

How the South Carolina calendar is built

Clemson’s planting chart has one pair of columns for the Coastal region and one for the Piedmont, each with a spring range and a fall range. Its footnotes mark the crops that are planted from transplants and the crops where sequential planting extends the cropping season.

Starting cucumbers indoors

How early to sow indoors depends on the crop more than the state, and the saved sources agree on the shape if not the numbers; UNH’s figure is 3 to 4 weeks.

Only UNH puts a number of weeks on cucumbers; the Minnesota row in the table is a handling tip, not a schedule.

In the garden itself, UNH sows cucumbers once the soil reaches 70 °F, which a soil thermometer answers better than any calendar.

Indoor start for cucumbers: what each saved source says (one row per source, none averaged)
Source	What it says
University of New Hampshire	3 to 4 weeks from seed to transplant; 1 to 2 weeks after the last frost is safe to set out
University of Minnesota	Cucumbers and squash transplant poorly, so raise them in fiber or paper pots that break down in the soil

Where the frost dates fall in South Carolina

NOAA’s 1991-2020 normals give nine probability levels for each station; the table keeps only the middle one, the even-odds date, and the links open the rest.

Regions in the last column come from the source’s wording, never from our reading of a map.

NOAA 1991-2020 normals for South Carolina stations: 50% last spring and first fall 32°F dates
Station	Last spring 32°F	First fall 32°F	Region in South Carolina’s calendar
Charleston International Airport, South Carolina	March 7	November 27	Coastal
Columbia Owens Downtown Airport, South Carolina	March 13	November 19	Coastal
Greenville Downtown Airport, South Carolina	March 16	November 20	Piedmont
Florence Regional Airport, South Carolina	March 19	November 13	Coastal
Rock Hill York County Airport, South Carolina	March 31	November 4	Piedmont

Worked example

Pick Greenville Downtown Airport, South Carolina as the garden. Half of recent years saw their last spring 32°F night by March 16, and half saw their first fall one by November 20.

Here the window starts April 15 (30 days after the median last freeze) and ends June 5 (81 days after it), under the Piedmont heading.

On the fall side, Piedmont’s last planting date of September 30 leaves 51 days before the November 20 median first freeze.

This is arithmetic on two printed figures, not a forecast: it moves with the year, and your own garden can sit weeks away from the station. Look up the station nearest you in the frost dates tool and repeat the subtraction.

Before you rely on these dates

The factsheet was last revised in February 2021.

Pencil the printed dates into a calendar, then adjust them after you have watched your own garden for a season.

Sources (4)