Advice About Japanese Beetles (and a Ray of Hope)

During the summer months I get hundreds of visitors a day looking for a way to get rid of Japanese beetles without resorting to hash chemicals. Japanese beetles are a frustrating pest, and there are few easy answers to getting rid of them. If you have them in your yard in great numbers, you have something beetle tasty, like roses, on your property to attract them. For me it's roses and asparagus.

I have an article for catching Japanese beetles early and using their scent to repel them: Control Japanese Beetles Naturally. This works pretty well if you catch them before they start coming out in large numbers. In zone 5, that would be around the middle of June. Your Cooperative Extension Office will know the date range for your area. Japanese beetles are b#@!$%s, but they're predictable.

If you missed the window, and lots of folks do, you can resort to traps. The only problem with this method is that to trap the beetles you have to attract them first. A trap will send the call out to all the beetles in your yard, the neighbor's yard and maybe even farther away than that.  The smart ones that don't make it into the trap stick around for lunch -- and dinner.

To be honest, I don't like pesticides or traps. I have pets, like having bees and butterflies around, and worry about birds and other wildlife being affected. Insecticidal soaps haven't worked well for me over the years either, and I refuse to put a veil (row covers) over my plants to keep the beetles out.


I only have one real light at the end of the tunnel to offer you. If you keep killing all the Japanese beetles you see by swatting them into a cup or bucket of soapy water, there'll be fewer around come fall. That means fewer grubs in your soil to cause problems next season. This really works pretty well. Early prevention plus diligent control the previous season (now) could mean very few Japanese beetles to bug you next spring and summer.

One way you can enhance the eradication efforts in your garden is by adding predatory (beneficial) nematodes.  These microscopic worms, once introduced to your soil, will kill the beetles in their grub stage so they won't be as much of a problem (your yard won't be a breeding ground and nursery for Japanese beetles over the winter.

I have almost eliminated the problem in my garden, and that's saying something.