Japanese Beetles and Controlling Them

Japanese Beetles on a plant leaf       Japanese Beetles are very destructive insects. As adults, they feed on over 300 species of plants and in the turf as grubs.

Adults emerge in May through June depending on the area. They fly to a plant, feed, release a pheromone and mate. This pheromone attracts others, so numerous beetles will be found in a small area.

After feeding occurs, the female flies to an area of turf and burrows down into the soil and lays 1 to 5 eggs. She re-emerges to feed, mate and lay eggs again. She repeats this until she has laid 40 to 60 eggs in a 6 to 8 week period.



Control of the adults is difficult due to how mobile they are. There are a couple of things you can do to improve control including using Fertilome Spreader Sticker in sprays and treat the soil under the plant and its foliage.

Systemic insecticides are very effective for use on non-edible plants. Treat as prescribed by the label and let it do the work. Fertilome Tree & Shrub Systemic Drench lasts the longest, Fertilome Rose & Flower Food with Systemic and Fertilome 2-N-1 with Systemic Insecticide offer other benefits as well as insecticide.

Also on non-edible plants: Hi- Yield 38 Plus is effective as a spray and Hi-Yield Turf Ranger works well on the soil beneath the plant. Use Hi-Yield Indoor/Outdoor Broad Use Insecticide for a non-systemic spray as directed on the label. Bonide Japanese Beetle Killer spray is available in a RTU spray bottle to treat small areas. Bonide Beetle Killer is available in a hose-end spray bottle that can cover up to 16,000 sq. feet. It will kill Japanese beetles plus other types of beetles.

For the fruit and vegetable garden, you can use Bonide Eight Home and Garden Insect sprays and dust as directed on the label. You can also use Rescue Japanese Beetle Traps. The trap uses floral scents, along with the beetle’s natural sex attractant to lure both male and female beetles to the trap. Once in the bag the beetles are trapped and cannot fly out. The trap should be placed on a post or stake 4’ above the ground at least 30 feet from ornamental plants, to lure beetles away from the area where they are creating damage.


Japanese Beetle Grub

JapaneseBeetleGrubWormsW       Japanese beetle grubs can be a very destructive pest in the lawn. Eggs hatch in 8 to 14 days and feed on turf roots, they winter over as a grub, pupate in the spring and emerge as an adult. As few as 7 to 15 grubs per sq. ft. can be damaging to a turf area.

Milky Spore is a natural product that kills the grub stage of the Japanese beetle. Milky Spore Powder contains Bacillus popillae, a bacterium that kills grubs by multiplying inside them, causing the grubs to die. It does not harm people, pets, bees, beneficial insects or the environment and is safe to use around waterways. Apply Milky Spore powder using  one teaspoonful every 4 feet in a checker board pattern on your lawn. There is a ten year performance guarantee on control of the Japanese Beetle Grub. The spore can remain in the soil for up to 20 years.

Bonide Annual Grub Beater contains 5% Imidacloprid, a systemic insecticide. Available in a 6 lb. bag that covers 5000 sq. feet and a 18 lb. bag that covers 15,000 sq. feet. It is applied once a year and it controls grubs all season long. It also kills European Crane Fly larvae, Billbugs, Mole Crickets, Cinch Bugs and other turf destroying insects. Apply any time, spring through summer.

Bayer Season Long Grub Control Spray is available in a hose end spray bottle that will treat 5000 sq. feet. Apply anytime in spring through late summer. Kills Japanese Beetle grubs plus larva of Mole Crickets & European Crane Flies. Contains 1.47 % Imidacloprid.

Visit us for help with the product that will work best for you.


Life Cycle of the Japanese Beetle





16 Responses to Japanese Beetles and Controlling Them

  1. Thanks Sandi! Very informative, I just squish them between my fingers!!

  2. Hillermann says:

    Thank you for your comment! It is always good to have some feedback. Have a good summer!

  3. Linda says:

    Loved the info for these pesky bugs, maybe with all the rain we have had, they got flooded out of the ground!!

  4. Arleen Doll says:

    Somebody told me you have a bag you can hand and it will draw the beetles and kill them. Do you?

  5. Hillermann says:

    Yes, we do carry a Japanese beetle trap, which is a bag that holds a scented bait that attracts the beetles, then they get trapped in the bag and die. The traps are $8.99 each. Thank you for your question.

  6. Carol Venable says:

    I have a bag trap I purchased from Hillermann’s .. works GREAT!

  7. Brenda Cabrera says:

    Here’s what I have heard about the traps:
    The problem is, the traps attract about four times as many beetles as would normally be in your yard, and only 50% to 75% of them will actually end up in the bag. The rest bounce off and make their merry way into your garden, where they vigorously set about munching your plants and laying plenty of eggs for next year’s beetles.

    We spray Sevin at the first sign of them and we have no issues after that.

  8. Hillermann says:

    Thank you for your comment Brenda. Different people are able to choose their preference with these methods. That is why we have several listed. Some would prefer non-chemical methods and the traps work well without the use of chemicals. We know many people who have had good success with the Rescue brand Japanese Beetle traps. They should be hung around 4 feet off the ground about 30 feet from the plants and gardens you want to protect. This will draw them away from the plants and they get trapped in the bag. They cannot get back out to lay eggs once they are trapped and numbers will be reduced the following year and each year traps are used. We have staff members who have had success with the Rescue Japanese Beetle traps.

  9. tj says:

    Hello Sandi, thank you for all of the information! Out of these methods, which is the organic method? I’d rather not use insecticides in my garden/landscape if I can. The Japanese Beetles did a lot of damage to my roses and linden tree this year and I’d like to start controlling them before next season. Thank you.

    • Hillermann says:

      Hi TJ, Rescue brand Japanese Beetle traps work good for reducing the numbers of the beetles without spraying insecticides. You hang the traps around 4 feet high off the ground and about 30 feet away from the plants you want to protect so it draws the insects away from the plants. The Rescue traps have a zipper seal at the bottom so that you can empty the trap into a trash bag (tie up the bag so beetles that have not died yet do not escape. Then, hang the trap back up to catch more beetles. Put out the traps each year and the number of beetles will be reduced each year. Another way to remove the beetles is to hand pick them off your plants and put them in a bucket with soapy water let them die and dispose of them after that.

  10. Charlaine Macey says:

    When do the beetles become active, regarding their destruction of plants, and how long does that period last before they stop being pest?

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