How to Get Rid of Japanese Beetles on Shrubs
You walk outside to admire your flowering shrubs and notice that some of the leaves look like lace. Unfortunately, this is not a new decorative garden trend. Japanese beetles may be having lunch in your yard.
Japanese beetles are shiny, metallic-looking insects that often appear during the summer. They can gather in groups and feed on the leaves, flowers, and fruit of many garden plants. If they are not controlled early, they can leave your favorite shrubs looking rough in a hurry.
The good news is that you do not always need to reach for the strongest pesticide on the shelf. A few simple steps can help reduce the damage and protect your garden.
How to Identify Japanese Beetle Damage
Japanese beetles are fairly easy to recognize. Adult beetles have metallic green bodies with copper-colored wings. You may also notice small white tufts of hair along the sides of their bodies.
The damage is often even easier to spot. Japanese beetles eat the soft tissue between the veins of a leaf. This creates a thin, skeletonized appearance. In severe cases, the leaves may look brown, scorched, or almost transparent.
Common plants that may attract Japanese beetles include:
- Roses
- Crape myrtles
- Fruit trees
- Grapevines
- Berry plants
- Japanese maples
- Some flowering shrubs
Not every plant is equally appealing to these pests. A garden with a variety of shrubs and flowers is usually less vulnerable than a landscape filled with only one type of plant.
Remove Japanese Beetles by Hand
For a small garden, hand-picking is one of the easiest and most practical ways to control Japanese beetles.
Fill a small bucket or container with water and add a little dish soap. Walk through the garden and gently knock the beetles into the container. The soapy water prevents them from escaping.
This method works especially well in the morning when the beetles are often less active. Check your shrubs regularly because new beetles may arrive after you remove the first group.
It may not be the most glamorous garden chore, but it is simple, inexpensive, and does not require spraying chemicals on blooming plants.
Avoid Placing Beetle Traps Near Your Shrubs
Japanese beetle traps are easy to find in stores, but they may not be the best solution for a small yard.
The traps use attractants to draw beetles toward them. While they may catch plenty of insects, they can also bring more beetles into the area. Some of those beetles may stop for a snack on your shrubs before they ever reach the trap.
If you decide to use a trap, do not place it beside the plants you are trying to protect. Keep it well away from your favorite shrubs and garden beds.
Keep Your Shrubs Healthy
Healthy shrubs are better able to tolerate minor insect damage. Water your plants deeply during dry weather, add a proper layer of mulch, and remove weeds that compete for moisture and nutrients.
Avoid overfertilizing damaged plants during extreme summer heat. Too much fertilizer can push new, tender growth that may attract more feeding and require additional water.
You should also prune away severely damaged or diseased branches when appropriate. Always use clean pruning tools and avoid removing too much foliage at one time.
Be Careful With Insecticides
If Japanese beetles are causing serious damage and hand-picking is not enough, an insecticide labeled for Japanese beetles on ornamental plants may be an option.
Always read and follow the product label carefully. Do not assume that more product will work better. Avoid spraying flowers while bees and other pollinators are active. Applying insecticides carelessly can harm beneficial insects along with the pests you are trying to control.
If a shrub is blooming heavily, consider removing beetles by hand first. This can help protect pollinators that may be visiting the flowers.
What About Japanese Beetle Grubs?
Adult Japanese beetles are only part of the problem. Their larvae, known as grubs, live in the soil and feed on grass roots. Large numbers of grubs can damage lawns.
However, treating your lawn does not guarantee that adult beetles will disappear from your shrubs. Adult beetles can fly in from nearby lawns and other areas.
If you notice both lawn damage and large numbers of beetles, contact your local extension office for advice about the best grub-control options for your area.
Check Your Garden Regularly
Japanese beetle damage is easier to manage when you catch it early. Walk through your garden every few days during summer and inspect the leaves and flowers of your favorite shrubs.
Look closely at roses, crape myrtles, fruit trees, and other plants that have been damaged in the past. Removing a few beetles early is much easier than dealing with a large group later.
Final Thoughts
Japanese beetles can be frustrating, but they do not have to ruin your garden. Begin with the simplest solution: inspect your shrubs regularly and knock the beetles into a bucket of soapy water.
Keep your shrubs watered, mulched, and healthy. Be cautious with traps and insecticides, especially around blooming plants. With a little consistency, you can reduce Japanese beetle damage and keep your flowering shrubs looking their best throughout the summer.