Japanese beetles (Popillia japonica) are invasive pests that can seriously damage gardens and crops. They feed on the leaves, flowers, and fruit of many plants, and their larvae harm lawns by eating the grass roots.
Though they’re sometimes confused with ladybugs, Japanese beetles have distinct features. They’re about half an inch (12 mm) long, with shiny metallic green bodies and copper-colored wing covers. You’ll also notice small white tufts of hair along the sides and back of their abdomen.
Damage from Japanese beetles is easy to recognize. Leaves often look “skeletonized,” with only veins remaining, flowers have ragged, chewed petals, and fruits may show holes or scars. In lawns, brown or dead patches usually mean larvae are feeding on grass roots.
If Japanese beetles are troubling your garden, try one of these natural ways to get rid of them.
Handpick Them
If small numbers of are present, the quickest and most effective way to remove them is to pick each one off by hand and drop it into a bucket of soapy water to kill it.
The beetles appear from late spring onwards, so make a regular plant inspection part of your daily routine to stop this garden menace in its tracks.
Try Companion Planting
Some plant species, such as garlic, chives, , rue, larkspur, and tansy, can repel Japanese beetles. To reduce the risk of damage, grow these plants in and around more susceptible plants.
Incorporate Trap Crops
Certain plants, including , white geraniums, evening primroses, and , are highly attractive to Japanese beetles and will draw them in large numbers. Grow a patch of sacrificial plants to lure Japanese beetles away from other crops; the beetles can then be collected and killed.
Neem Oil
kills adult Japanese beetles, their larvae, and eggs. Use it as a targeted spray in problem areas where Japanese beetles have been seed-feeding. Avoid widespread spraying of , as it can also harm beneficial insects.
Garlic Spray
The smell of garlic is a great way to deter beetles and many other troublesome garden pests. Peel a few cloves, blend them in a with a cup of water, and strain into a . Reapply frequently for maximum effect.
Grow Resistant Plant Varieties
To reduce the amount of Japanese beetle control, you need to grow plants such as boxwood or holly that are less attractive to Japanese beetles.
Attract Natural Predators
Plant nectar-rich flowers to encourage beneficial insects like tachinid flies and , which prey on Japanese beetles. Alyssum, cilantro, dill, daisies, and are preferred food sources for these beneficial insects that serve as natural pest controls.
Insecticidal Soap
only works on contact and has no residual activity, so it must be sprayed directly onto every Japanese beetle you spot. When used carefully, this method is non-toxic to other beneficial insects.
Attract Birds
Install birdhouses to attract birds such as robins and cardinals that feed on Japanese beetles. Robins prefer a secluded nesting area, such as a dense hedge, where they can raise their young without being disturbed.
Prune Infested Branches
Damaged leaves give off chemical signals that attract even more Japanese beetles to your garden. Regularly inspect plants and crops and carefully prune away any damaged leaves or branches.
Row Covers
When the larvae turn into adult Japanese beetles, they quickly fly to their preferred feeding sites. To minimize damage, protect vegetable crops with horticultural fleece or fine mesh row covers.
Kaolin Clay
forms a thin barrier that prevents Japanese beetles from feeding on leaves. This is available in a spray that is simple to apply and gives instant results when used in areas prone to Japanese beetle infestations.
Essential Oils
Essential oils like , wintergreen, or lavender are known to repel Japanese beetles. Mix a few drops of oil with water in a and a small amount of to help it disperse, and spray affected plants daily.
Watering Control
Japanese beetle grubs thrive in moist soil. Reducing moisture levels can help limit their development. To reduce Japanese beetle populations, switch to drought-tolerant plants and grasses and keep watering to a minimum.
Bacillus thuringiensis
Bacillus thuringiensis is a biological insecticide that targets Japanese beetle grubs in lawns and gardens. Although highly effective, certain strains of Bacillus thuringiensis have been shown to harm monarch butterfly populations and should not be used in gardens where these endangered insects are present.
