How to Get Rid of Japanese Beetles
A metallic green beetle with copper-brown wing covers that skeletonizes the leaves of roses, grapes, linden and hundreds of other plants. Its white grubs feed on grass roots in lawns. If you are seeing them in gardens and on plants and in lawns and grass, the steps below will help you clear them out and keep them from coming back.
Quick answer
- Hand-pick beetles in the early morning and drop them into soapy water
- Protect prized plants with fine netting during peak flight in early summer
- Treat lawns for grubs in late summer only if grub counts are high
Japanese beetles do not bite or sting people; the harm is to plants and turf.
Confirm you have Japanese beetles
Correct identification matters, because the right fix for Japanese beetles differs from the fix for their lookalikes. Adults measure 10–15 mm (up to about 0.59 in) and are usually green, metallic and brown. Look for these features:
- Metallic green head and thorax with coppery wing covers
- Five tufts of white hair along each side of the abdomen
- Feeds in groups, leaving lace-like skeletonized leaves
They are most often confused with June bug and emerald ash borer. See the full Japanese beetle profile for side-by-side details.
Why you have Japanese beetles
Japanese Beetles are drawn to the specific plants they feed on and multiply quickly in warm weather. Planting the same crop in the same bed each year makes outbreaks worse. Broad-spectrum sprays can kill the predators that would otherwise keep them in check. They are most active in summer, so expect to see more of them then.
When you'll see Japanese beetles
Japanese Beetles are most active in summer. Summer heat speeds up development, so populations can grow quickly.
Typical places to check: garden or plants and lawn or grass.
Step-by-step: getting rid of Japanese beetles
Step 1: Hand-pick beetles in the early morning
Hand-pick beetles in the early morning and drop them into soapy water. Repeat this for at least two to three weeks, since eggs and hidden insects keep appearing for a while.
Step 2: Protect prized plants with fine netting during peak flight in early summer
Protect prized plants with fine netting during peak flight in early summer. Keep notes on where you still see activity so you can focus your effort.
Step 3: Treat lawns for grubs in late summer only if grub counts are high
Treat lawns for grubs in late summer only if grub counts are high. Keep notes on where you still see activity so you can focus your effort.
Natural and low-toxicity options
These methods work well alongside the steps above and keep chemical use to a minimum:
- Hand-pick pests or knock them into a bucket of soapy water.
- Use floating row covers as a physical barrier.
- Attract beneficial insects with flowering herbs such as dill, yarrow and alyssum.
- Try insecticidal soap, neem oil or Bt products labeled for this pest, following the label.
If you do use a pesticide, choose one labeled for this pest and the place you're treating, and follow the label exactly. The label is the law.
When to call a professional
Most home gardens can handle Japanese beetles without a professional. Contact your local cooperative extension office if damage is severe or you can't confirm the pest.
How to keep Japanese beetles from coming back
- Rotate crops and clean up plant debris at the end of the season.
- Inspect plants weekly, especially leaf undersides.
- Keep plants healthy with proper watering and spacing.
- Encourage birds, ladybugs, lacewings and parasitic wasps.
Safety notes
Japanese beetles do not bite or sting people; the harm is to plants and turf.
Keep children and pets away from any traps, baits or treated areas.
About beetles
The Japanese beetle is one of the beetles. Beetles go through complete metamorphosis: egg, larva (grub), pupa and adult. The larval stage often does the most feeding and damage, and it can last from a few weeks to several years depending on the species. Adults protect their flight wings under hard wing covers called elytra, which is why most beetles look armored and meet in a neat line down the back.
Look closely at larvae as well as adults. Grubs in soil, fuzzy larvae in closets and small worms in flour are all beetle larvae, and finding them tells you where the problem is centered.
Frequently asked questions
What is the fastest way to get rid of Japanese beetles?
Hand-pick beetles in the early morning and drop them into soapy water. Most people see a clear drop in activity within one to three weeks when they combine this with sealing entry points and removing whatever attracts them.
Are Japanese beetles dangerous?
Japanese beetles do not bite or sting people; the harm is to plants and turf.
When are Japanese beetles most active?
Japanese Beetles are most active in summer.
What do Japanese beetles look like?
Metallic green head and thorax with coppery wing covers. Adults measure 10–15 mm (up to about 0.59 in).