WATCH YOUR BOXWOOD

SCOTT: Mike, I just received a notice from one of our suppliers, Fertil-Lome, at Black Diamond Garden Center. They were giving all of their midwest customers a heads up of a very invasive insect that can knock out boxwood shrubs in a matter of one season. Have you heard anything about this?
MIKE: I had the opportunity to review your notice. Initially, I thought they were talking about the Boxwood Psyllid. That insect has created havoc, along with spider mites, with boxwoods in previous years. By laying eggs and cupping the leaf, protecting the larvae from natural predators. As they mature, the larvae would suck the life out of the plant and possibly kill it. And now this! The Box Tree Moth! Will it ever end? 
SCOTT: After reading this notice, I discovered that this moth is very difficult to control. Can you tell me just where the Box Tree Moth came from?
MIKE: Scott, the Boxwood Tree Moth is native to East Asia and discovered in Ontario, Canada along with New York in 2021. Instead of killing the plant by sucking the chlorophyll out like the Boxwood Psyllid, these larvae chew your boxwood leaves. They are voracious eaters and once the primary food source is gone, the leaves, they resort to eating the bark. Thus, girdling the plant. They can entirely defoliate a boxwood in less than one season. We have information that they have been causing irreparable damage in southeast Michigan and are headed our way.
SCOTT: Is there any way to either to protect our boxwood hedges or if our plants are infested, can we knock the insect out?
MIKE: The safest way to control the caterpillar is to use a natural insecticide called Bacillus Thuringiensis, better known as “BT” or one can also safely use “SPINOSAD.” Spinosad is another natural insecticide used to control caterpillars, Thrips and some beetles. Spinosad disrupts the larvae nervous system causing paralysis and death. Spinosad is derived from natural sources and is understood to be much less toxic to humans, birds and mammals. The downside is the eggs and caterpillar hide on the underside of the leaves of the boxwood. Making it difficult to reach the pest. So, get as much of the underside of the leaf as possible. Please repeat each application every four to six weeks.
SCOTT: Four to six weeks all summer long?
MIKE: Yes, all summer for this moth, as they have many generations appearing each year. If ou think you may have the beginning stages of a “Box Tree Moth” on your boxwood and you are a bit apprehensive of applying any pesticides to your landscaping, please contact a licensed company to discuss your options.
SCOTT: If it’s too late to save your Boxwoods, a great replacement alternative is the Inkberry Holly bush. They have a very similar appearance and can be pruned/shaped like you did your boxwoods. Plus, they grow fast and they are native.
MIKE: And they are pollinator friendly, which boxwoods are not. Nice bonus!
Your Midwest Garden Podcast guys, Mike O’Rourke and Scott Sandstrom, share gardening advice with readers throughout the growing season. O’Rourke, retired from Black Diamond Garden Center and known as the Garden Guy for many years, discusses landscape issues with Sandstrom in a casual conversation designed to educate listeners, and now readers, on a wide variety of topics.