Japanese Beetles

Japanese beetles. Those words strike fear in the heart of gardeners. These 3/8-inch-long metallic green beetles with copper-brown wing covers emerge from the ground in June. Individual beetles live about 30 to 45 days, concentrating their activity over a four- to six-week period beginning in July.

Japanese beetles can feed on about 300 species of plants, but roses appear to be a favorite food. They usually feed in groups, starting at the top of a plant and working downward, and prefer plants exposed to direct sunlight. The adults chew out leaf tissue between the veins, giving the leaves a skeletonized appearance.

Mark recommends Cygon, a highly effective systemic insecticide which can also be used to control lace bugs, iris borer, leaf miners, whiteflies, aphids, leafhoppers, bagworms, mites and even houseflies.

The organic way to control Japanese beetles is to hand pick the insects and drop them into soapy water, later disposing of them. The presence of beetles on a plant attracts more beetles, so be vigilant and pick them off right away. Traps are not recommended because they tend to lure more beetles to your landscape, and only a portion of the beetles attracted to traps are caught in them.