Corn is a warm-season crop widely grown across Georgia, but successful planting depends on selecting the correct time to sow seeds. Optimal timing balances avoiding late spring frost with ensuring the soil is warm enough for quick germination. Planting at the right moment maximizes yield and helps the corn escape the worst of the summer’s pest and disease pressure. A successful harvest requires matching the planting date to the specific geographic location and variety of corn chosen.
Defining Planting Zones Across Georgia
Georgia’s climate varies significantly from the mountainous north to the coastal south, dividing the state into distinct agricultural zones with different planting schedules. The three main regions—North, Central, and South Georgia—experience last frost dates that can differ by up to six weeks. This variation is due to differences in elevation and distance from the Atlantic Ocean and the Gulf of Mexico.
North Georgia, including the Appalachian foothills, has the shortest growing season and the latest average last frost date, often extending into late April or early May. Central Georgia, encompassing the Piedmont region, has a moderate season. South Georgia, characterized by the Coastal Plain, enjoys the longest growing window, with the last frost often occurring in late February or early March.
Timing the First Planting (The Spring Crop)
The soil temperature is the primary factor for spring corn planting, and it must be consistently warm for several days before sowing. Corn seed germination is slow and erratic if the soil temperature at a two-inch depth is below 60°F. Planting when the soil is 60–65°F ensures prompt emergence and prevents the seed from rotting in cool, wet soil conditions.
In South Georgia, the earliest planting window typically begins in late February to mid-March, as this region meets the soil temperature requirement first. Central Georgia gardeners should aim for a planting window between mid-March and mid-April. This timing allows the crop to pollinate and mature before the most intense summer heat arrives.
Planting should be delayed in North Georgia until the soil consistently warms, which often pushes the window into mid-April or early May. Seeds should be sown approximately one inch deep in cool soil, or up to one-and-a-half inches deep as the soil warms later in the season. Proper wind pollination is maximized by planting seeds 8 to 12 inches apart in short blocks of at least three rows, rather than a single long row.
Selecting Corn Varieties for Georgia’s Climate
The choice of corn variety should be guided by its suitability for Georgia’s long, hot, and humid growing season. Sweet corn is the most common choice for home gardeners and is categorized by its sugar genetics: standard sugary (su), sugary enhanced (se), and supersweet (sh2) types. Sugary enhanced varieties, such as ‘Silver King’ or ‘Kandy Korn,’ are often favored by home growers for their superior flavor and tender kernels.
Supersweet varieties, like ‘Incredible,’ retain their sweetness longer but require isolation from other corn types to prevent cross-pollination that can result in starchy kernels. Field corn, which is primarily grown for livestock feed or milling, is less sensitive to cross-pollination. When selecting any variety, gardeners should look for a shorter “days to maturity” (DTM) rating if planting late, or select varieties with specific resistance to regional diseases like Southern Corn Leaf Blight.
Succession Planting and Second Crops
To extend the fresh harvest window beyond the initial spring crop, gardeners can use succession planting by making multiple smaller plantings throughout the season. This method involves sowing a new batch of corn every two to three weeks until the final cut-off date. Alternatively, planting varieties with differing days to maturity all at once can also stagger the harvest.
The planting of a second crop is limited by the need for the corn to reach maturity before the first fall frost. For Middle Georgia, corn must be planted no later than mid-to-late July to ensure the ears are fully formed and ready for harvest. Later plantings, especially those made during the peak of summer, demand increased attention to moisture and pest control. Corn requires a minimum of one inch of water per week, with deep irrigation being particularly important during the pollination and ear-filling stages.