How to Control Earworms in Corn

Plant corn early in the season so that it ripens early. Corn earworm caterpillars lay eggs in August and September at the time when most corn is beginning to silk out. Emerging larvae enter the corn through the opening of the silk for their favorite treat. Planting corn so it ripens before eggs are laid prevents corn earworms from attacking your corn.

Apply mineral oil to the silk on your corn when it first appears. Repeat once a week until the silk turns brown and corn is ripe. According to the University of California's Integrated Pest Management Services, mineral oil controls both eggs and larvae.

Encourage natural enemies of the corn earworm to keep the population under control. Birds, toads and ladybird beetles feed on corn earworms and may reduce infestations.

Secure the end of the ear with a clothespin or a tightly twisted elastic once silk has formed to prevent larvae from entering the corn. Although it is not a foolproof way to prevent infestation, it may work as a deterrent, according to University of Illinois Extension.

Use pesticides, if necessary, to prevent damage from corn earworms. The Integrated Pest Management Services from the University of California recommends dusting the tip of the corn ear with carbaryl when the silk first emerges. Repeat each week until the silk turns brown.