Why Are Spotted Beetles Eating My Green Bean Plants?

Beetles most commonly damage the leaves of the green beans.

Many home vegetable gardeners plant rows of green beans, as they grow well in many areas. However, like any vegetable in the home garden, certain pests may cause damage to the foliage of growing green beans. The Mexican bean beetle and the bean leaf beetles are the most common beetles found on green bean plants.

Identifying the Culprit

The key to controlling any garden pest is proper identification. The Mexican bean beetle are a coppery-red color with small black spots forming on the wings, according to the North Carolina State University Extension. The bean leaf beetle are a yellowish-brown with black spots on the wings and a black triangle on the wings.

Damage

Both the bean leaf beetle and the Mexican bean beetle feed upon the leaves of green bean plants. Mexican bean beetles create lace-like patterns on leaves by eating the tissue between leaf veins. Bean leaf beetles most often eat young leaves and sometimes the outside pods of the beans.

Control

Monitor the garden for signs of beetle activity. Handpick beetles from plants in order to minimize the damage. For widespread damage, consult the local agricultural extension office to determine the best insecticides for use in your yard.

References

• North Carolina State University Extension: Pests of Beans and Peas
• University of Minnesota Extension: Bean Leaf Beetles in the Home Garden