Paige Pelini, co-owner of Mother Earth Gardens in Minneapolis, calls it "the morning beetle pick." She starts her day with a cup of coffee in one hand and a bucket of water in the other, knocking voracious Japanese beetles off plants to halt the munching that turns healthy leaves into veined skeletons.
Last year was the first Pelini battled a massive invasion of the bronze-winged beetles. "Before that it was just a smattering," she said. But this year has been even worse. "They're thick. It's not been pretty."
Japanese beetles feed on many plants this time of year, but some of their favorite noshes include grapevines, roses, lindens and apple trees. While the beetles are bugging some local gardeners more than ever, the pests' presence is similar to last year, according to Jeff Hahn, entomologist at the University of Minnesota. "The last five or six years, we've seen a gradual increase in their numbers as they gradually expand their territory."
But the adult beetles appear to have emerged earlier than usual, thanks to the mild early spring.
"I started getting reports in mid-May; usually it's a July 1 insect," Hahn said. The good news is that the beetles' wave of destruction is short-lived. "The numbers are heavy for six to eight weeks, then start to decline. It wouldn't surprise me if they taper off in early August."
If you don't want to wait that long, there are things you can do to banish beetles. "There's not an easy solution, but there are a lot of tactics," Hahn said.
You can do what Pelini does: pluck the bugs off plants and drop them into a bucket of soapy water. "Make sure they fall into it," Hahn said. "They like to drop and play dead, but they'll just come back." The best time to do it is in the morning when the beetles are less active, he said.
Another nonchemical remedy is to cover plants with netting or cheesecloth while the beetles are at their peak, Hahn suggested.