Just as many of us are gathering boxwood to make lovely Christmas decorations there is news of a new blight that has infected boxwoods in neighboring Connecticut. It is caused by the fungus Cylindrocladium buxicola, which hails from the UK.
No one knows how it entered the U.S., but it has been found in North Carolina, Virginia, and now, landscapes and garden centers in Connecticut.
The fungus infects boxwood leaves, producing brown spots. The leaves then turn brown and drop. It also infects the plants’ stems, leaving black lesions. The blight does not affect the roots, and infected plants can survive, if they are not repeatedly defoliated.
Boxwood blight spreads quickly, especially when it’s warm and damp. The spores are carried by rain and wind over short distances, but the disease is carried far and wide when infected plants which appear healthy are transported.
Control measures include meticulous sanitation around the plants, frequent inspections, making sure there’s enough space between plants, fungicides, and avoiding overhead watering.
If you find infected plants, pull them immediately, and here in Rhode Island, bring a sample to the University of Rhode Island’s plant clinic for a diagnosis. For more details on this blight, go to this University of Connecticut website.
And please be careful with the boxwoods you use for your holiday decorations. You don’t want to accidentally spread this disease or introduce it into your own landscape!