The time at which vegetables are planted outdoors depends on the cold hardiness of a particular species or cultivar. Vegetables can be divided into two categories based on temperature requirements: cool-season and warm-season crops.

Cool-season vegetables originated in temperate climates and have their favorable growth period during the cool parts of the year. Cool-season crops grow poorly in summer heat. Though cool-season crops continue to grow well past the earliest freeze in the fall, they should be started early enough to mature before hard freezes are expected.

Warm-season crops primarily came from subtropical and tropical regions and require warm weather for seed germination and plant growth. They are injured or killed by freezing temperatures and should not be planted outdoors in the spring without protection or until the danger of freezing temperatures is past. Warm-season crops planted in the summer to mature in the fall should be planted early enough so they can be harvested before the killing freeze in the fall.

To determine when to plant cool- and warm-season vegetables in South Carolina, refer to Table 1. Knowing the number of days required to reach maturity, a gardener could determine the appropriate planting time for seeds and transplants by using the average dates of the first and last freezes in their area.

Piedmont: Abbeville, Anderson, Cherokee, Chester, Edgefield, Fairfield, Greenville, Greenwood, Lancaster, Laurens, McCormick, Newberry, Oconee, Pickens, Saluda, Spartanburg, Union and York counties.
Central: Aiken, Allendale, Bamberg, Barnwell, Calhoun, Chesterfield, Clarendon, Darlington, Dillon, Florence, Kershaw, Lee, Lexington, Marion, Marlboro, Orangeburg, Richland and Sumter counties.
Coastal: Beaufort, Berkeley, Charleston, Colleton, Dorchester, Georgetown, Hampton, Horry, Jasper and Williamsburg counties.

1 Dates shown are for the upper coastal plain and lower piedmont. In western North Carolina delay planting 10 to 20 days in spring. In eastern North Carolina plant 7 to 14 days earlier in the spring and 7 to 10 days later in the fall.
2 At these temperatures germination and emergence should be rapid. Planting at lower soil temperatures would delay or prevent germination.
3 Seeding depths and soil temperatures are given for gardeners who wish to grow their own plants.
4 Set plants with at least 50 percent of their length below ground.
5 Carries resistance to verticillium wilt, fusarium wilt, and root-knot nematodes.

© Erv Evans, Consumer Horticulturalist
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