Japanese Beetles On Impatiens
Bill; Troy, MI asks: I live in an apartment and every May, I plant several containers with impatiens on my balcony. I buy fresh potting soil every spring to fill these containers. In the past two years I have had a problem with Japanese beetles overtaking my potted plants. I treat with an insecticide, but it seems the flowers don't grow as well after I use this product. It gets rid of the beetles, but I sacrifice the full lush impatiens I have grown before the beetle problem arose. Is there some way I can prevent these beetles from taking over my plants?
Dear Bill: Japanese beetle populations are cyclical. They come and they go and beetle populations rise and fall. Having been in the lawn care business for nearly 35 years, we learned to chart Japanese beetle activity as it moved to various areas in a city. Some neighborhoods would get slammed with Japanese beetles, while nearby neighborhoods would be totally passed over. After a couple of years the situation might reverse. We could almost predict what parts of the city would be hit by Japanese beetle outbreaks from year to year.
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The beetle populations will eventually fall to their normal levels as predators like birds, rodents and other insects and parasite populations feast on the burgoning beetle population. It may take a couple of years to see this occur.
Lots of people use those Japanese beetle Bag-A-Bug traps containing a power sex attractant. These traps are meant to cover extremely
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There are various pesticides labeled for spraying the grub of the Japanese beetle and general sprays that are labeled for treating adult beetles. Treating the adults will require repeated applications. Of course, there's a downside to treating the plants. Not only will you kill off the Japanese beetles, but you'll also kill off beneficial insects that eat aphids and mites. Seems like you just can't win this one.


