The Best Methods for Japanese Beetle Control

Filed under Plants, Misc by Lauren Cook on .

Seen any of these guys in your garden lately?

 Chances are, you have because they are back in Southern Illinois just in time for summer. The nasty bugs can completely defoliate an ornamental plant in a very short period of time. You have a few options when it comes to avoiding Japanese beetle damage. To avoid “Beetle Frustration”, choose the option that works best for you.


Japanese Beetle Traps


How does it work?

Most Japanese beetle traps contain two chemicals used to attract beetles, a sex pheromone and a floral lure. These two combined make the traps attractive to local Japanese beetles.


How effective is it?

Japanese beetle traps may end up attracting more beetles than they actually trap. For best results, avoid hanging the traps in your garden. To be effective the best place to hang a trap is at the farthest edge of your property (if you have a lare yard), or if you and all of you neighbors agreed to hang a trap within their each of your gardens.


Milky Spore


How does it work?

Milky spore, or Paenibacillus popilliae, is a soil-borne disease that kills the white grubs of japanese beetles in lawns. There are several products available for innoculating your soil with milky spore. Milky spore is not harmful to beneficial insects, birds, bees, pets nor man.


How effective is it?

Milky spore can effectively rid your lawn of the white grubs of Japanese beetles. However, when the white grubs become adult beetles, they can fly in from neighboring yards that have not yet been innoculated, rendering the time and money spent ineffective in preventing damage to your desirable landscape plants by Japanese beetles.




How does it work?

Chemicals such as carbaryl, acephate and permethrin are availabe to homeowners for effective Japanese beetle control. Insecticides will poison the beetles once they start to eat your plant. Spraying every 10 – 14 days, according to the directions on the pesticide label, during the months of June and July will keep your plants out of harm's away.


How effective is it?

Sevin, a common insecticide containing the chemical carbaryl, can be extremely effective in preventing Japanese beetle damage. Especially, if you begin a preventative spraying before the beetles have had a chance to cause severe damage.




How does it work?

Manually remove the Japanese beetles from the plant and kill them immediately. Some gardeners prefer to carry a bucket of soapy water with them in the garden. The beetles will die when immersed in the soapy water.


How effective is it?

Hand-removing Japanese beetles from your garden plants is labor-intensive, but very effective. This method would probably not be recommended for severe infestations. Hand-picking is safe for beneficial insects and birds.


Avoid Desirable Plants


How does it work?

Avoid planting plants that Japanese beetles are known to feed on, including:



Crape Myrtle





How effective is it?

By avoiding the above plants, you will lessen your chances of a Japanese Beetle attack. Although you could not guarentee that you will never find a Japanese beetle on other plants, if you want to avoid using pesticides or the maintenance of removing the pests from your plants, your best bet is to learn the “likes” and “dislikes” of Japanese beetles and avoid the “likes”.