FrostCal

When to Plant Onions in South Carolina

In a typical South Carolina location, start seeds indoors Jan 11 – Jan 25, then transplant outdoors Feb 22 – Mar 8. Across the state, the outdoor planting window starts as early as Jan 7 in Charleston and as late as Mar 23 in Gaffney.

Method Start indoors, then transplant
Days to maturity 90–120 days

Start seeds indoors 8-10 weeks before last frost (or use sets/transplants); set out 2-4 weeks before last frost, very cold-tolerant as seedlings.

Onions Planting Dates by City

CityStart indoorsTransplant
ColumbiaJan 5 – Jan 19Feb 16 – Mar 2
CharlestonNov 26 – Dec 10Jan 7 – Jan 21
North CharlestonDec 27 – Jan 10Feb 7 – Feb 21
Mount PleasantJan 2 – Jan 16Feb 13 – Feb 27
Rock HillJan 16 – Jan 30Feb 27 – Mar 13
GreenvilleJan 17 – Jan 31Feb 28 – Mar 14
SummervilleJan 11 – Jan 25Feb 22 – Mar 8
SumterJan 13 – Jan 27Feb 24 – Mar 10
Goose CreekDec 27 – Jan 10Feb 7 – Feb 21
Hilton Head IslandDec 23 – Jan 6Feb 3 – Feb 17
FlorenceJan 8 – Jan 22Feb 19 – Mar 5
SpartanburgJan 28 – Feb 11Mar 11 – Mar 25
Hilton HeadDec 23 – Jan 6Feb 3 – Feb 17
Myrtle BeachJan 10 – Jan 24Feb 21 – Mar 7
AikenJan 8 – Jan 22Feb 19 – Mar 5
GreerJan 17 – Jan 31Feb 28 – Mar 14
AndersonJan 12 – Jan 26Feb 23 – Mar 9
MauldinJan 17 – Jan 31Feb 28 – Mar 14
GreenwoodJan 15 – Jan 29Feb 26 – Mar 12
North AugustaDec 19 – Jan 2Jan 30 – Feb 13
TaylorsJan 17 – Jan 31Feb 28 – Mar 14
Saint AndrewsJan 5 – Jan 19Feb 16 – Mar 2
ConwayJan 4 – Jan 18Feb 15 – Mar 1
EasleyJan 21 – Feb 4Mar 4 – Mar 18
SimpsonvilleJan 18 – Feb 1Mar 1 – Mar 15
Wade HamptonJan 5 – Jan 19Feb 16 – Mar 2
LexingtonJan 14 – Jan 28Feb 25 – Mar 11
SocasteeJan 4 – Jan 18Feb 15 – Mar 1
HanahanDec 27 – Jan 10Feb 7 – Feb 21
BlufftonDec 23 – Jan 6Feb 3 – Feb 17

Showing the 30 most populous of 58 South Carolina cities. Dates are estimates from each city's NOAA frost normals and university extension timing guidelines. See all South Carolina cities.

Frequently Asked Questions

When should I plant onions in South Carolina?

In a typical South Carolina location, start seeds indoors Jan 11 – Jan 25, then transplant outdoors Feb 22 – Mar 8. Across the state, the outdoor planting window starts as early as Jan 7 in Charleston and as late as Mar 23 in Gaffney.

When is the last frost in South Carolina?

The average last spring frost in South Carolina ranges from February 4 in Charleston to April 20 in Gaffney, based on NOAA 1991–2020 climate normals.

How long do onions take to grow?

Onions typically take 90–120 days from planting to harvest. Start seeds indoors 8-10 weeks before last frost (or use sets/transplants); set out 2-4 weeks before last frost, very cold-tolerant as seedlings.

Other Crops in South Carolina

When to plant onions in other states

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