Caution if decorating with boxwoods

Posted: December 10, 2013

Special to The Winchester Star

The boxwoods on left that have box blight are at a nursery. The photo on right shows leaf spots on the plants due to the blight.
Boxwoods with the blight are shown in a landscape.

Winchester — Anyone decorating with greenery, including new plants, wreaths, and or other trimmings for the holidays, should check with the supplier to ensure their purchase does not contribute to boxwood blight, which has been found in other parts of the state, according to two horticultural experts.

Boxwood blight is a fungus that can cause complete defoliation of plants and is difficult to control. In Virginia, the disease was first found in Carroll County in 2011 and has now spread to Chesterfield County, the city of Richmond, and more recently Fairfax County, according to Mary Ann Hansen, an extension specialist with the Virginia Tech Plant Disease Clinic in Blacksburg.

The clinic provides plant disease and diagnostic services to agents with Virginia Cooperative Extension. Hansen recently sent out an update about boxwood blight to VCE agents across the state.

Most boxwood cultivars are susceptible to the disease, particularly English and American boxwoods, but some cultivars appear to have a tolerance for the disease. For homeowners, that means the while plants may not show obvious symptoms, they can still harbor spores that could infect nearby susceptible plants, she said.

There have not been confirmed specimens with the disease in this area, but VCE wants to educate the public to slow the spread of the disease, which poses a great threat to boxwoods, according to Mark Sutphin, associate extension agent for Frederick County, Agricultural and Natural Resources, Horticulture.

“The bottom line is to be very careful when introducing any boxwood into your landscape — as greenery for holiday trimmings or as new plants,” he said.

This recommendation is particularly appropriate to historic sites and homes with majestic boxwoods in the landscape, he said. These same sites are likely to decorate with live greenery during the holidays and need to be aware of this threat.

Not only during the holidays but throughout the year, it’s advisable to purchase boxwood greenery or new boxwood plants from reputable suppliers where boxwood blight has not been found, said Hansen.

Ask the retailer if the greenery/plants come from a supplier in the Boxwood Blight Cleanliness Program. Growers in this program follow strict best management practices along with routine inspections from the Virginia Department of Agriculture, she said.

All incoming boxwood greenery and plants should be inspected for leaf spots, leaf browning, black streaks on stems, and leaf drop. Wreaths should be assembled away from existing boxwoods in the landscape. And any new boxwood plants should be isolated from existing boxwoods for at least a month and monitored for disease development, she advised.

Following the holidays, boxwood greenery should not be composted or discarded on site, said Sutphin. Instead, it should be bagged, preferably double bagged, and taken to the landfill.

Information

For more information, contact the local Virginia Cooperative Extension office, where additional control recommendations can be offered and questionable samples can be submitted to the Virginia Tech Plant Disease Clinic. In Frederick County, call 540-665-5699 or emailgreenhelpline.frederickco@gmail.com.

— Teri Merrill is resident of Winchester and master gardener with Virginia Cooperative Extension.