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How to Fertilize Sweet Corn

corn field image by Liz Van Steenburgh from

Sweet corn is a fast-growing vegetable that is usually low-maintenance when it comes to fertilizer. Fertilizer helps raise the level of nutrients in the soil to harbor a beneficial growing environment for corn. Corn enjoys a nitrogen-rich soil environment with enough phosphorus. Growing well-fertilized corn involves attention to preparing the bed for the corn seeds and a keen eye to watch for signs of nutrient deficiency during growth.

Spread a 2-inch layer of compost over the area in which you will plant the corn.

Lightly sprinkle organic nitrogen fertilizer over the layer of compost.

Mix the compost and nitrogen fertilizer mix with the ground soil until the compost/soil mix is about 5 to 7 inches deep.

Plant the corn according to planting instructions for your strain of corn.

Fertilize the plants with a natural liquid corn fertilizer when the corn plants have reached a height of 4 inches. Fertilize the plants again when they are around 10 inches tall.

Fertilize Sweet Corn With Nitrogen

Break up your garden soil with a spade, removing any rocks and debris and smashing up any large dirt clumps. Spread 10 pounds of compost for every 50 square feet of gardening space and mix it thoroughly into the top 6 inches of soil. Compost doesn't just add nitrogen, but also various micronutrients while improving the soil structure and enhancing drainage. Plant the corn, irrigate it and begin standard sweet corn care practices. Mulch helps conserve water in the soil and helps ensure consistent soil moisture levels, which sweet corn plants love. Fertilize the sweet corn again once it is 6 inches tall by applying 1/2 lb. of 46-0-0 nitrogen fertilizer for every 100 square feet of garden space.


Liquid fertilizer for corn can be organic or chemical. The fertilizer is a solution that usually contains about four parts nitrogen to three parts potassium and three parts phosphorus. The solution is diluted with water before it is used to fertilize the corn.


Keep an eye out for purple leaves on your corn, a condition which indicates that your corn needs more phosphorus. Spraying the corn plants with a liquid seaweed spray during the cold months of the planting season is a common treatment for phosphorus-deficient purple corn leaves.

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