If you don’t feel like using chemicals in your garden, you can control Japanese beetles naturally. There is the old standby, knocking them into a bucket of soapy water with a stick. They will be unable to fly out of the soapy water and will drown eventually. Usually the little holes that insects use to breath, called spiracles, are too small for water to enter, but the soap fixes that problem. This procedure works best during the cooler parts of the day when the beetles are less likely to fly away from the plants.

A naturally occurring bacteria called Milky Spore kills Japanese beetle grubs which feed underground on grass and plant roots (ha ha, they’re getting you from the ground up). It is safe for beneficial insects, pets, and children. The bacteria spreads slowly through the soil, killing beetle larvae for many years. Milky Spore is sold as a dust which may be called Doom, Grub Attack, or Grub Killer. It is more effective in warmer areas of the country where the soil stays warm most of the summer (USDA Hardiness zones 6-10).