Japanese beetles (Popillia japonica) are notorious garden pests that can cause significant damage to a wide range of plants, from early June to late August. These invasive scarab beetles are identifiable by their metallic green heads and copper-colored bodies. They feed voraciously on leaves, flowers, and fruits, often skeletonizing foliage and leaving a disfigured appearance. Japanese beetles are not only destructive but also harmful to beneficial insects and pollinators, making them a double threat to garden health. However, by strategically choosing the right plants, you can minimize the risk of an infestation.
Understanding Japanese Beetles
Japanese beetles are opportunistic feeders, preferring plants with large flower petals, smooth foliage, and a light sweet scent. They are particularly attracted to fruit trees and garden plants with these features. While it can be challenging to predict exactly which plants will fall victim to these pests, understanding their preferences can help you choose plants that are less likely to be targeted. Identifying these characteristics is a crucial step in preventing damage in your garden.
1. Roses (Rosa)
Roses are a favorite target of Japanese beetles due to their fragrant, large blooms. These pests are particularly fond of munching on rose petals and surrounding leaves, creating a lace-like skeleton effect that significantly detracts from the plant’s appearance. If you are reluctant to part with the beauty of roses, consider these alternative plants:
Top Rose Alternatives & Companion Plants That Japanese Beetles Avoid:
- Lilac (Syringa): The sweet, intoxicating scent of lilacs makes them an excellent alternative to roses. Japanese beetles generally steer clear of these shrubs.
- Pachysandra (Pachysandra): A low-growing evergreen ground cover that can be planted around roses to create a barrier against beetles.
- Magnolia (Magnolia): Large, showy flowers that bloom in the spring and are less attractive to Japanese beetles.
2. Crape Myrtle (Lagerstroemia)
Crape myrtle’s vibrant blooms and pollen-rich flowers make it a popular choice for pollinators, but they also attract Japanese beetles. While they support beneficial insects, these beetles can cause significant damage by munching on the blooms and seedpods. To enjoy crape myrtle’s beauty without attracting beetles:
Top Crape Myrtle Alternatives & Companion Plants That Japanese Beetles Avoid:
- Forsythia (Forsythia): This early-blooming shrub offers nectar for pollinators in spring, attracting bees, butterflies, and birds without attracting beetles.
- Catmint (Nepeta): Its strong scent helps repel Japanese beetles, making it a great companion plant.
- Milkweed (Asclepias): Provides food for pollinators while keeping beetles at bay.
3. Hibiscus (Hibiscus)
The large, attractive flowers of hibiscus, especially varieties like Rose of Sharon, are a magnet for Japanese beetles. These pests target the soft, supple leaves surrounding the blooms, leading to unsightly damage. To maintain the stunning appearance of hibiscus without attracting beetles:
Top Hibiscus Alternatives & Companion Plants That Japanese Beetles Avoid:
- Poppy (Papaver): These colorful flowers offer a similar aesthetic appeal without the beetle issues.
- Stonecrop (Sedum): A drought-tolerant succulent that is not favored by Japanese beetles.
- Cranesbill (Geranium): Contains a substance that temporarily paralyzes beetles, making them easy to remove.
4. Hollyhock (Alcea)
Hollyhocks are a staple in cottage gardens but are also a prime target for Japanese beetles. These pests will feed on nearly every part of the plant, potentially harming pollinators like butterflies and hummingbirds. To keep your cottage garden beautiful and beetle-free:
Top Hollyhock Alternatives & Companion Plants That Japanese Beetles Avoid:
- Foxglove (Digitalis): Its toxic nature deters beetles from feeding on it.
- Columbine (Aquilegia): These old-fashioned garden favorites are resistant to beetles and deer.
- Tickseed (Coreopsis): This cheerful flower deters Japanese beetles and thrives in cottage gardens.
5. Japanese Maple (Acer palmatum)
Japanese maples are prized for their lacy foliage and vibrant fall color, but they are also vulnerable to Japanese beetles. These pests target the tender leaves, leading to unsightly skeletonization and potentially attracting more insects. To maintain the beauty of your Japanese maple:
Top Japanese Maple Alternatives & Companion Plants That Japanese Beetles Avoid:
- Arborvitae: A fast-growing evergreen that can complement the aesthetics of a Japanese maple without attracting beetles.
- Burning Bush (Euonymus alatus): Offers stunning red foliage in the fall without attracting beetles.
- Inkberry Holly: A native evergreen that provides year-round green foliage while deterring Japanese beetles.
What is the Best Plant Spray for Japanese Beetles?
If switching plants isn’t an option, organic insecticides like neem oil can help control Japanese beetle populations. Neem oil is effective against beetles while being safe for bees and other beneficial insects. Additionally, handpicking beetles and disposing of them in soapy water can be an effective method, though it may not be the most convenient option for all gardeners.
Can I Avoid Japanese Beetles by Choosing Spring-Blooming Plants?
Yes, planting spring and fall-blooming plants can help reduce the damage caused by Japanese beetles during the summer months. By choosing plants that bloom outside the typical Japanese beetle active season, you can keep your garden largely free from these pests throughout the summer.
