Mexican bean beetles overwinter as adults on trees, shrubs, or in plant debris. In early spring some adult beetles end their hibernation and begin feeding and throughout the spring more adults will continue to emerge from hibernation. Females lay eggs in yellow-orange clusters of 40 or more on undersides of leaves. Each female will lay an average of 460 eggs. Pupation occurs on leaf surfaces.
Adults appear in less than two weeks to begin the cycle again.
The timespan from egg to adult beetle is about one month and multiple generations occur annually in Virginia. Clean up plant debris after harvest. Applications of a botanical insecticide may also help reduce mexican bean beetle populations. Treat with a registered insecticide when damage first appears. Direct sprays to undersides of leaves.