Planting date is a critical component in maximizing corn yield and profitability. Optimal planting window is generally from March 10 to April 1 in north Louisiana. Corn’s yield potential when planted later than recommended may be reduced due to climatic constraints such as temperature fluctuations and day length as well as increased disease and insect pressure. Seven hybrids were planted mid-March, mid-April and mid-May on two Mississippi River alluvial soils, Commerce silt loam and Sharkey clay, to evaluate grain yield potential and seed quality. Lowest grain yields occurred at the mid-May planting date regardless of year, hybrid or soil. Dates to mid-silk and physiological maturity declined linearly as plantings were delayed. Test weight, kernel weight and kernels per ear also declined with delayed planting. Ear rot and grain insect damage increased between the mid-March and mid-May plantings. Foliar diseases were not significant in either year of the trial.