Corn Leaf Blight

Corn Leaf BlightPhoto Credit: Margaret Tuttle McGrath, Cornell University

Northern corn leaf blight appears on corn leaves as distinct, grayish green to tan blotches or streaks up to 6″ long. Southern corn leaf blight causes smaller tan spots with reddish brown borders. Young corn plants are most susceptible to these fungal diseases, and if the infection is severe the plants may die.

Corn leaf blight is usually associated with commercial corn plantings. Wet, humid weather favors the spread of the disease and under these conditions corn leaf blight may also infect backyard corn plantings. The fungus overwinters on infected plant debris in the soil.

Prevention and Control

  • Plant blight-resistant varieties, such as Sugar Buns. Purchase only certified disease-free seed.
  • Rotate corn to avoid planting it in the same location more than once every three years.
  • Clean up the garden at the end of the growing season
  • Compost infected cornstalks in a hot compost pile (material must reach the disease-killing temperature of 150 degrees F for several days) or destroy them.

Last updated: 12/15/2022