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Japanese Beetles Are Here!

Japanese Beetle Damage
Japanese beetles will damage trees, shrubs, fruits and roses

Over 30 Solutions

Japanese Beetles are here. Getting a head start is the only way to be sure your plants are safe from this destructive pest. Gertens experts have over 30 solutions to control these pesky insects. Japanese Beetles can be destructive toward plants in both their adult beetle stage and in their grub larval stage.

Japanese Beetles are an incredibly destructive plant pest found throughout most of the eastern United States, stretching westward toward states along the Mississippi River, including Minnesota. As adults they damage plants by feeding on foliage of a multitude of trees, shrubs, fruits, ornamentals, flowers, vines, and vegetables.

Some of the more notable plants they feast on in the Twin Cities metro area are; rose bushes, grape vines, birch and linden trees, and raspberries. The damage can be identified by skeletonized leaves (eating the area between a leaf's veins) and large holes in leaves, this can often appear to be a lacey texture. The Japanese beetle grub lives in the soil and causes destructive damage by eating the roots of many plants including turf grasses.

Adult Japanese Beetles are most commonly found during the late spring through late summer. While female beetles are feeding, they will periodically leave the plants and lay eggs, usually into the turf. One beetle can lay upwards of 50 eggs a year. These eggs then hatch into grubs around midsummer which begin to feed on the roots of turf grasses and other plants.

Bonide Japanese Beetle Killer

Before the first frost, the grubs will bury deeper into the soil and remain inactive throughout the winter. When the ground thaws in the early spring, the grubs will move closer to the surface of the soil and begin feeding on roots again until they begin to pupate in late spring. Then, in about two weeks the pupae become adult beetles and they emerge from the ground and begin consuming plants again. This completes the average, one year life cycle.

If Japanese Beetles are bugging you, consider one of our many different solutions to help control the infestation.

Eight Insect Control

One solution is spraying plants that are already infested with the adult beetles with an insecticide. We have several effective sprays for this type of treatment. Bonide makes a product simply called Japanese Beetle Killer; which is a natural pyrethrin based insecticide for use on vegetables, flowers, ornamentals, trees & shrubs. Another effective spray treatment is one more product from Bonide called, Eight Insect Control. Eight Insect Control kills Japanese beetles on contact and also has a residual effect, lasting up to a week or more. We also have a few options that can be used around your fruits and vegetables and can both be used up until the day of harvest. One product is Natural Guard Insecticidal Soap.The other product is from Fertilome and is called Triple Action Plus.

Another product for control of the adult Japanese Beetle is Systemic Insect Spray by Fertilome. It kills insects and prevents new infestations.Controls Adelgids, Leaf Beetles (including Elm Leaf Beetles and Viburnum Leaf Beetles), Vine Weevils Larvae (including Black Vine Weevils), Leafhoppers (including Glassy-Winged Sharpshooter), Roundheaded Borers (including Asian Longhorned Beetle and Eucalyptus Longhorned Borer), Flatheaded (including Bronze Birch Alder, and Emerald Ash Borers), Leafminers, Mealybugs, Pine Tip Moth larvae, Japanese Beetles, Adult, Psyllids, Lacebugs Royal Palm Bugs, Sawfly Larvae, Scales (includes Armored Scale [Suppression] and Soft Scale), Thrips, and Whiteflies. This solution dissolves in water, moves down through the soil, and is absorbed by the roots. Once absorbed, it moves up through the tree or shrub, providing year-long protection even into new growth.

Green Thumb has a product to control the grub stage of the Japanese Beetle.

Bonide Beetle Bagger

Their Season Long Grub Control kills grubs all season long. Apply late May through mid August for best results. It stops the feeding activity immediately and kills quickly. If applying insecticides isn't your thing, or if you are just looking for an easy way to help fight the Japanese beetle problem, look no further than using our Japanese Beetle BaggerTrap by Bonide. This trap attracts beetles with a dual floral/pheromone lure into a plastic, hourglass-shaped bag. The lure effectively attracts beetles from a surrounding area of up to 5,000 square feet. The trap might attract more Japanese beetles to the immediate area, so be sure to hang it about 15' away from any trees or plants you are trying to protect.


If you have any further or clarifying questions about Japanese Beetles or other insect or plant related issues, please give us a call at 651.450.1501 or stop in to our Lawn & Garden department and we'll be more than happy to help solve any insect or yard and garden problems.