Spreading the planting dates and maturity groups can help with planting and harvesting operations. If conditions allow, corn needs to be planted at optimum time. The most active planting for South Carolina is between March 20 and April 20. Planting usually begins in early March.
If many acres of corn need to be planted, start planting when the conditions allow it, so the planting can finish within the optimum planting time. Calendar date and soil temperature are reliable indicators for making the decision on when to begin planting corn. Some other advantages of early planted corn include higher soil moisture at planting, lower temperatures during pollination, earlier maturity and harvest in the fall, and higher yield and test weight potential. Early planting dates result also in faster canopy closure in the growing season, better stalk quality, and may help reduce late insect and disease pressure.
When planting, start with full-season hybrids first, and then plant early-season and mid-season hybrids. The full-maturity hybrids would have the benefit of maximum heat-unit accumulation. Delaying planting of full-season hybrids would reduce yields more than other short- and mid-season hybrids. Therefore, use short- or medium-season hybrids, instead of full-season hybrids, when planting late. However, planting corn late in the growing season increases the insect and disease pressure, and the risk of low corn yields due to pollination occurring during a period of high temperature and moisture stress.
Higher grain yields are usually obtained when corn is planted as early as weather conditions permit. Higher yields of early planted corn are mainly due to reduced pest pressure late in the season, better rainfall patterns, and cooler air temperatures during corn silking. Start planting corn when soil temperature reaches about 55oF at 2 inch depth in the morning and the weather forecast indicates a good chance of warm temperatures over the next few days. Soil temperature will depend on soil type and moisture content.
Light sandy soils will warm up faster than heavy and wet soils. Also, planting should be delayed by 3-5 days if planting in the no-till system due to plant residue and higher moisture. Corn should be planted during optimum moisture to support traffic without causing soil compaction and mudding the seeds. Frost may still occur following planting, but corn normally withstands frost damage to above ground tissue, since the growing point is still below the soil surface until corn reaches V5-V6 stage (about 12 inches).