They feed on soybean leaves and a variety of other legumes, mate and lay eggs. Each female may lay 175 to 250 orange-colored eggs in clusters of ten to thirty in the soil at the base of soybean plants. Larvae feed on below-ground plant parts and eventually pupate in earthen cells. Adult beetles emerge to feed on bean pods and foliage until they begin hibernating in the fall. Green cloverworms pass the winter in either the pupal or adult stage.
Females lay single eggs on the undersides of the soybean leaves.
Eggs produce green worms that feed on these leaves for about four weeks before dropping to the ground to burrow into the leaf litter or soil where they pupate. Adult moths emerge to start the second generation. Japanese beetles overwinter in the soil as the third larval stage and, as the soil warms, move closer to the surface to feed on fine rootlets. Females burrow into loose, moist sod to deposit eggs. The eggs hatch after a few weeks and the grubs feed on rootlets until cold weather arrives.