Japanese beetles can be a nuisance in your garden and around your yard. Often they appear in late June and populations rise when the soil is moist. They can sometimes last until September. Recent rain has caused more of these beetles to climb out of the soil and to get on your favorite plants. You can use an insecticide to kill these pests, but it may kill beneficial insects as well and start other problems.
An easy remedy is to get a mason jar and fill it about three-fourths the way with soapy water and to knock the beetles into it. Traps can be used but can bring in more beetles than they will catch. Traps are useful if it’s a community-wide goal to reduce the population. Clean traps every 2 days to make sure they remain effective. It is best to start using traps early, put traps out when you spot your first beetle. Be sure to set traps away from your favorite plants.
You can sample for the grubs of these beetles in September by digging a 12-inch square box that is approximately 3 inches deep. You will flip the grass over to see the roots. If you see more than 10 of these white grubs treatment may be necessary. If you are looking for plants that are resistant to these beetles you can plant Hickory trees, Dogwood trees, Lantana, and Lily-of-the-Valley.