How to Plant Corn in Containers

Prepare half-barrels for corn planting after the final frost of winter. The root system of a corn plant is quite large and the 28-inch diameter and 18-inch depth of a standard half-barrel is big enough to handle it.

Set the half-barrels in an area that receives at least six hours of sunlight each day, filling them three-quarters of the way full with organic potting soil. Corn favors soil with a pH between 6.0 (slightly acidic) and 7.0 (neutral). Organic potting soil is a sterile, airy soil with a neutral pH.

Press four corn seeds (kernels) 1 inch into the soil. Sow the seeds 4 inches apart and 4 inches from the barrel's walls. Water in the corn seeds with a garden hose, just enough to dampen the soil to a 1-inch depth. Maintain this level of moisture up until the point of germination -- five to seven days.

Maintain moist soil as the corn seedlings grow, supplying at least 1 inch of water per week with a garden hose. Pluck out the two weakest seedlings in each container, leaving behind the healthiest two, when the seedlings reach a height of 4 inches. Remove the healthier of the final two when each seedling reaches 8 inches.

Fill the area between the barrel's rim and the soil line with a layer of bark mulch or straw. Mulching suppresses weeds, which will compete with the corn plants for water. Mulching also improves water retention, which will help keep the soil moist.

Feed container-grown corn a diet of 12-15-15 fertilizer. Follow the manufacturer's suggestions in regard to allocation amounts and frequency. Corn appreciates a dose of fertilizer each week to improve vigor.

Harvest the corn when the ears mature. Harvest time for corn varies depending on variety -- usually between 60 and 90 days. Three weeks after the tassels develop and turn brown is the best time to harvest corn.