I have written about the annual invasion of Asian multi-colored lady beetles a number of times. Remember these are the lady bugs that bite … well, pinch anyway. The introduced aphid fighters do good work during the growing season, but they don’t like to spend North American winters outside. And no matter how well you think your house is sealed, when the cool weather comes, you will find several to vast numbers of these orange, black and cream colored beetles on your ceilings, walls, floors, lights, curtains and virtually every other beetle-friendly place in the house. Although they are little more than a nuisance, if you disturb Asian multi-colored lady beetles they emit an unpleasant-odor-producing liquid that also stains. If you just squash them, they leave a mark on your lovely white walls and ceilings. What to do?
Until now, about the only thing you could use to fend off the Asian lady beetle invasion was a vacuum. I have already dumped several dust-buster-bin sized loads of beetles this year. But, thanks to Agriculture Research Service scientists, I can now add catnip to my limited invasion-fighting arsenal.
According to ARS scientists, catnip oil contains compounds that naturally repel the beetles without harm. In one extensive study, 95 percent of adult male and female lady beetles altered their course when they encountered filter paper impregnated with nepetalactone, one of many compounds found in catnip oil.
So, do you need to purify the nepetalactone, or at the very least extract catnip oil from your catnip to repel the Asian lady beetles this fall? ARS scientists haven’t yet made that jump, however since catnip is easy to grow and lovely to look at in the garden, why not harvest a short ton of the feline-frolic-inducing herb and place dried bundles of it inside your storm windows, and the other lady beetle landing zones that are truly hot? If dried catnip doesn’t work on the beetles, you can always toss the bundles to your feline friends and enjoy a good show.
Read more about the possibility of using plant secondary products to deter Asian multi-colored lady beetles here.
Hank Will raises hair sheep, heritage cattle and many varieties of open-pollinated corn with his wife, Karen, on their rural Osage County, Kansas farm. His home life is a perfect complement to his professional life as editor in chief at GRIT and Capper's Farmer magazines. Connect with him on Google+.