Having a nursery of our own at Van Zelst, Inc. we strive to stay on top of new plant diseases and insect pests. The topic that many growers in our area have been discussing is boxwood blight. With the number of boxwood that we grow, pass through our nursery, and our crews install every year, we are watching the spread of this disease and routinely inspecting our own stock.
Boxwood blight is a fungal disease that affects many members of the Buxaceae family including Buxus (boxwood), Pachysandra (Japanese spurge), and Sarcococca (sweet box). This disease was first found in the United Kingdom in the mid-1990s and made its way to the U.S. in 2011. The University of Illinois Plant Clinic first confirmed this disease in 2016 in Lake and Cook counties.
Boxwood blight is characterized by leaf spots, stem cankers, and defoliation. There are other diseases that show these symptoms, but total defoliation of the plant is unique to boxwood blight. When the leaf spots are first developing they are circular light or dark brown spots with a yellow ring around the outside. These spots will expand and take over the entire leaf. The stem cankers have a linear shape and are dark brown to black. Defoliation starts at the base of the plant and works its way to the top.
By now you must be wondering, what options do you have if your boxwoods are suffering from this disease? Often infected plants are removed and disposed of in local landfills. In some cases, all boxwood on a property must be removed. Treatments are becoming available.
If you are a home owner in Lake or Cook counties or the surrounding areas with preexisting boxwood, you may not have too much to worry about. The 2016 cases were from new plants brought into the landscape purchased from garden centers and landscapers. When purchasing boxwoods, you need to assure that you’re not introducing diseased plants to landscape. If you suspect that you have boxwood blight, please contact the Illinois Department of Agriculture or you can send a sample to a University of Illinois Extension office for a small fee (information can be found here: Additional Boxwood Blight Information).
When using Van Zelst for your next landscape renovation you can sleep soundly at night knowing that our nursery only sends out the highest quality plants. Growing 90% of our stock, we put a lot of time into making sure that we are growing strong, healthy plants. Having our maintenance crews on your property weekly will help with early detection of this disease, so that you have the most options available for treatment.