How to Grow Corn in a Container

Corn (Zea mays) often proves challenging to grow in containers. Not only is it a large plant requiring plenty of space, it is also particular about its growing conditions and care. Container cultivation may not produce a bumper crop of corn, but it will produce enough to give gardeners with limited space a taste of summer. It is vital, however, to choose the right type of corn and the correct container to ensure a successful harvest.

Standard-sized corn cultivars grow too large for container cultivation, so smaller varieties work best. Early, short-stalked varieties such as Early Sunglow (Zea mays "Early Sunglow") and Precocious (Zea mays "Precocious") work well because they bear early in the season and stay relatively small. Miniature varieties like Golden Midget (Zea mays "Golden Midget"), Candystick (Zea mays "Candystick") and On Deck (Zea mays "On Deck") also thrive under container cultivation, although their ears are smaller than early-bearing varieties, which is another factor to consider. Be sure the miniature variety you select produces more stalks than just one.

Corn needs rich, deep soil and eight to 10 hours of sunlight each day to perform well. A large, draining container that holds at least 10 gallons of loamy, fast-draining soil for every four plants will work for corn, but it must be at least 21 inches wide and 8 to 12 inches deep. Mix in 1/2 tablespoon of granular 10-10-10 analysis fertilizer for every gallon of soil in the pot. For example, a 10-gallon pot requires 5 tablespoons of fertilizer. Start at least a dozen corn plants to ensure a good yield, sowing the seeds roughly 4 inches apart at a depth of 1 inch once soil temperatures warm to at least 65 degrees Fahrenheit. Once the seedlings reach a height of approximately 6 inches, thin the plants to a spacing of 8 inches. To ensure good pollination of the corn plants, plant several containers of miniature corn and group them close together.

Regular watering is vital to successfully growing corn, especially in a container. Sun and wind exposure combined with limited soil capacity mean corn will lose water faster than if it is grown in the ground. Check soil moisture daily and water whenever it feels barely damp 1 inch below the surface. Run a hose on low volume until water flows from the bottom of the container. Check the moisture level twice on especially hot days and water, if needed. Avoid shallow watering because it encourages shallow roots, which will decrease the corn's ability to withstand harsh conditions and encourage toppling.

Corn feeds heavily throughout its life cycle whether grown in the ground or in a container. Container-grown corn is especially susceptible to nutrient deficiencies because of its limited soil reserves and the loss of soil nutrients from constant watering. Feed the plants with a water-soluble fertilizer with an N-P-K analysis of 15-15-15. Mix 1 teaspoon of fertilizer with 1 gallon of water and replace one watering per week with the solution. If signs of nutrient deficiencies such as purple or pale leaves develop, increase feeding to twice weekly.