Are Japanese Beetles Bugging You?!

Published by Bucks Country Gardens in Lawn & GardenWhat's Happening

Anyone who knows me knows that I cannot handle the sight of bugs. And if you’re one of the few who didn’t already know, the hoots and hollers coming from my desk when something buzzes about would certainly give my phobia away. Right now, the mere thought of creepy crawlers has me twitching with anxiety as I swat away at imaginary insects. I think I’d prefer to see a field mouse scurry across the floor than a stinkbug fluttery passed me. Why, then, am I tackling the topic of Japanese Beetles? Granted, the image research on the internet for this blog has me seriously reconsidering this assignment…  But I digress… Because everyone needs to know. Everyone needs to know how to eradicate them… How to prevent them… How to keep them from devouring your landscape and precious plants.

Now is the time to be enjoying your outdoor living space. You did all of the hard work in the spring and the time to relax is now. But you can’t. There are Japanese Beetles flying all around and they’re destroying your beautiful roses, the delicate leaves of the Japanese Maples, gorgeous flowering blooms of Crape Myrtles… Here are a few ways to help combat the beetles now plus a few other tips to make next year more beetle-free.

But first, a (very) brief history of the Japanese Beetle. Much like it’s name implies, this dark green and bronze-winged beetle originated in Japan. How it came to America is similar to many a tale of other foreign insects’ arrival in the States. It is believed that Japanese Beetle larvae hitched a ride on a shipment of iris bulbs from Japan to a nursery in Riverton, NJ around 1916. Since there are a lot of natural predators and environmental conditions in Japan, the beetle population there is kept in check. In the United States, it’s a different story. Today, Japanese Beetles are well established in every state east of the Mississippi River, excluding Mississippi itself and Florida. I’m sure those two states are doing the happy dance. A few isolated infestations have been found in a hand full of mid-western states.

In order to effectively fight the beetles, it helps to understand where and when to find them before they are flying about. If you are already finding evidence of Japanese Beetles on your plants (look for skeletonize leaves), then save this information for next year. It won’t help you now, but the next paragraph certainly will. Beetles are the adult form of grubs and begin to show their presence around the 4th of July. Grubs are found in turf. They are white and curl up in a c-shape. They feed underground on the roots of your lawn until they mature to beetles. Damaged areas from heavy grub feeding become thinned out and brown spots appear, eventually causing the turf to not be well anchored and easily rolled back like a carpet. Check for grubs in May and August. Should you find them, use Bonide All Season Grub Killer to eradicate them while in the grub stage. Eggs and newly hatched grubs need moisture to prevent drying out, so be sure limit watering of lawns should you spot grubs.

If you currently have active adult beetles in your garden, there are a number of ways to help control them and limit their damage. The use of traps is very effective and lures beetles in large numbers. What is most important to remember about traps is to place them about 30’ downwind of your garden. Do not place them near plants they find tasty… you’ll simply be inviting them to a plant buffet. Another product that’s a proven winner, Milky spore, is a bacterial-based method to keep your landscape beetle-free for a long time. Apply milky spore granules or powder to your lawn in spring, summer and fall and grubs will consume it during feeding. This disease also affects the larvae and they, too, will die off.

If you’re short on patience and longing for instant gratification, there are a number of sprays that eliminate beetles quickly by treating the leaves they eat with an insecticide. Sevin Ready-to-Spray Bug Killer simplifies the application process by providing an attachment on the bottle that hooks up directly to your hose. Bonide Bon-neem and Espoma Earth-tone are ready-to-use sprays that combine a fungicide, miticide and insecticide that control a variety of insects, diseases and mites all in one product.

Thinking proactively, another great way to reduce the chances of Japanese Beetles from taking up residence in your garden is to design your landscape with specific plants in mind. They are highly attracted to Roses, Flowering Cherries, Crape Myrtles, Purpleleaf Plum, Fruit Trees and Shrubs, Hibiscus, Canna and Zinnia, just to name a few. But if you add a few plants beetles find unappetizing to your garden, you can reduce the likelihood of them devouring your greenery. Some natural repellents are: Chives, Catnip, Garlic, Citronella, Hemlocks, Common Lilac, Hollies, Firs, Rhododendrons, Spruces, Yews and Box Elders. If your garden is already established with more mature trees and shrubs, perhaps adding a few deterrent plants near the more sought after ones will help to keep the beetles at bay.

Trees and shrubs have a good chance of recovering from beetle damage if they weren’t recently planted and aren’t under stress from other conditions such as poor soil or drought. So, setting aside my extreme discomfort with buggy situations, the fact remains that Japanese Beetles are voracious and destructive insects that must be controlled and eventually eliminated. If we all do our part, then maybe someday our precious gardens and landscapes will no longer be unwilling participants in a plant buffet fit for mighty pests. Now only if we can do the same with stinkbugs…

Original post appeared on July 18, 2014

Adriene Vesci | Graphic Design & Advertising Coordinator