Holiday Wreaths May Harbor Boxwood Blight

Boxwood tips are  used in holiday decorations, including wreaths. Carefully inspect wreaths in stores and garden centers before buying. Leaves and twigs may be infected with the boxwood blight fungus, and could be a source of infection for residential boxwood in Delaware.  Conditions of wet weather and high humidity have been favorable for boxwood blight in the Mid-Atlantic, where the serious blight has been confirmed.   The fungus Calonectria pseudonaviculata causes severe defoliation and death of container boxwoods, and dieback of in-ground plantings.  Most boxwood species are susceptible, including American and English boxwood (Buxus sempervirens), little leaf

Boxwood Blight – twigs showing blackened areas and leaf drop; Leaf spots due to boxwood blight.

boxwood (B. microphylla) and hybrids such as B. sinica.  Timely and accurate identification by microscopy is important for management of this aggressive disease.  If you suspect a wreath or decorative piece is infected with boxwood blight, dispose of it in a bag in the trash, do not compost or discard near foundation plantings of boxwood. Spores would be dormant at this time, but management consists of strict sanitation along with a diligent fungicide schedule over a couple of seasons.

N Gregory Dec 12, 2018