Boxwood blight threatens old, new plants

With fall planting in full swing and the holidays just around the corner, boxwoods — as plantings and decorations — are on many people’s minds.

But Virginia Cooperative Extension wants to raise a caution flag about the potentially hazardous blight that can afflict the boxwood plant, which is commonly used in decorative wreaths.

Boxwood blight, or box blight, is a fungal disease that attacks boxwood, resulting in defoliation and complete ruin of the plant.

“It can be a potentially devastating horticultural event,” said Kate Robbins, program assistant for agriculture and natural resources with James City County’s extension office. “Once the fungus gets in, it can take out the whole bunch.”

Blight is a relatively new disease, first discovered in the United Kingdom in the 1990s. The first case in the United States was reported in 2011. It made its way to Williamsburg in 2015 during the holiday season due to suspected infection from boxwood greeneries and decorations that were improperly disposed of after the season. The fungus ultimately spread to boxwoods in one backyard of a neighborhood in the city of Williamsburg, destroying 60 English boxwoods in that yard and spreading to other properties.

Many homes in Williamsburg have historic boxwoods that can be affected by the disease. Since that first incident in 2015, other blight cases have been reported to the extension office.

“We’ve had confirmed cases not just downtown, but also in every corner of James City County,” Robbins said.

Boxwood blight typically presents itself in the fall or spring when the weather is cooler. Symptoms include brown spots on the leaves that lead to defoliation as well as black streaking on the stem tissue. Some boxwoods may be carriers of the disease without showing any symptoms. The disease can be transferred to boxwood through landscaping and contaminated tools, new plants, or animals such as deer. Sweet box and pachysandra may also be carriers of blight.

Robbins encourages anyone who suspects their boxwood plants are infected to have the plant tested at VCE. Both James City County and York County have offices for testing. Samples should be double-bagged to avoid further contamination.

Homeowners should be cautious when introducing new boxwood plants to their yards since both English and American boxwoods are susceptible to blight. Make sure boxwood plants are purchased from a reputable nursery. If possible, avoid purchasing wreaths and other holiday decor made with boxwood since these can also harbor the blight pathogen.

The extension office recommends consumers do the following when buying greeneries and decorations for the holidays:

  • Inspect the greenery carefully for symptoms of boxwood blight. Do not introduce any symptomatic greenery to landscapes with boxwood.
  • Always double-bag any symptomatic plant material before discarding it. Be careful to remove all plant debris, including fallen leaves.
  • Once the holidays are over, dispose of boxwood greenery including any fallen leaves and debris properly by double-bagging it in sealed plastic bags and removing it to a landfill. Do not compost boxwood greenery.
  • Submit any potentially infected boxwood to the extension office for diagnosis.

“People need to watch out for their boxwood and recognize that blight can happen, then do the right thing with the disposal,” Robbins said.

Taking the proper actions to remove potentially affected boxwood can save residents and their neighbors a lot of trouble and heartache.

“It saddens me when people don’t follow through with the protocols for disposal and it ends up affecting their neighbors and neighborhood,” Robbins said. “We will never be able to eradicate boxwood blight, but we want to educate people about it.”

Want to know more?

Contact James City County cooperative extension at 757-564-2170 or the York County office at 757-890-4940.

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