Collect all boxwood debris from the ground, and either burn or bury the plants never compost them. If your shrubs test positive, there is no treatment. Double-bag three or four cuttings, each measuring 6 to 8 inches long, in sealable plastic bags, and ship them to the lab in a sturdy box. Branches, stems, and leaves damaged by the disease make the best samples.
#BOXWOOD BLIGHT TREATMENT PROFESSIONAL#
The only way to confirm if a plant has boxwood blight is to submit samples to a professional plant-disease diagnostic laboratory almost every state has one. But boxwood shrubs with cold or drought damage, Volutella canker, or root rot also display similar symptoms. Photo/Illustration: Courtesy of North Carolina State Universityĭark brown and black streaks or cankers on otherwise green branches, sometimes accompanied by white spores in humid conditions.ĭiscolored foliage and streaked stems are the first signs of boxwood blight. Boxwood (Buxus sp.) is a popular and widely grown woody ornamental that is deer resistant, mostly evergreen, and low maintenance with a relatively long lifespan in the absence of boxwood blight disease. But before plants turn completely brown and defoliate, there are a few early warning signs: Photo/Illustration: Courtesy of North Carolina State Universityĭark or light brown spots on leaves, often in a circular pattern. After a stretch of rain, infected plants may develop symptoms after just a few days. Boxwood blight spreads most rapidly when conditions are warm, humid, and shady. How quickly plants decline depends on weather conditions. Pay special attention during warm, humid periods with a lot of precipitation. TREATMENT Treat with appropriate fungicides from May onwards. Rain splash, overhead watering, and contaminated tools can all transmit boxwood blight to healthy shrubs. DAMAGE Large bare patches with withered leaves and branches occur, which may eventually lead to the complete death of the plant. As you’re buying boxwood this fall, be sure to carefully inspect each plant before making a purchase, and don’t ignore the disease’s early symptoms if you spot them in your garden. With still no cure in sight, the home gardener’s best line of defense is prevention. Although the roots remain healthy, infected boxwood looks dead, thanks to its bare branches. Although this fungal disease doesn’t typically kill its host plant, it does have a serious impact on the plant’s appearance-often stripping the shrub of its leaves completely. and cvs., Zones 4–9) and sweet box ( Sarcococca spp. and cvs., USDA Hardiness Zones 6–9) that researchers have tested are vulnerable, as well as other plants in the boxwood family, including pachysandra ( Pachysandra spp. All of the commercial boxwoods ( Buxusspp.
Since the first confirmed case in the United States about a year ago, boxwood blight (caused by Cylindrocladium pseudonaviculatum) has spread to 10 states and two Canadian provinces.