Boxwood Blight: What is wrong with my Boxwoods?

Boxwoods are popular evergreen shrubs that add beauty and structure to gardens. However, there is a looming threat that all garden enthusiasts need to be aware of - boxwood blight. This fungal disease, caused by the pathogen Cylindrocladium pseudonaviculatum, can quickly devastate boxwood plants and spread throughout an entire garden. In this blog post, we will explore what boxwood blight is, how it spreads, and what steps you can take to prevent and manage it.

What is Boxwood Blight?
Boxwood blight is a highly contagious fungal disease that infects boxwood plants. It originated in Europe and was first discovered in the United States in 2011. The disease primarily affects boxwoods in the Buxaceae family, including common boxwood (Buxus sempervirens) and Japanese boxwood (Buxus microphylla).

The symptoms of boxwood blight are easy to spot. Infected plants develop dark brown leaf spots, defoliation, and stem cankers. The spots often have a unique "bullseye" pattern, with a brown center surrounded by a yellow halo. These characteristic symptoms, along with black streaks on the stems, are telltale signs of boxwood blight.

How Does Boxwood Blight Spread?
Boxwood blight spreads through the dispersal of infected spores. The primary mode of transmission is through water splashing, commonly during rainfall or irrigation. The spores can also be transported by wind, animals, contaminated tools, and even clothing. Once introduced into a garden or nursery, boxwood blight can rapidly spread, infecting nearby boxwoods and potentially decimating an entire collection.

Another concerning aspect of boxwood blight is its ability to overwinter. The pathogen can survive on fallen leaves and infected debris, waiting for favorable conditions to establish itself again in the following growing season. This resilience makes boxwood blight a particularly persistent threat.

Prevention and Management Strategies
As with many plant diseases, prevention is key when it comes to boxwood blight. Here are some strategies to protect your boxwoods:

Choose resistant boxwood varieties: Some boxwood cultivars have shown increased resistance to boxwood blight. Research and select cultivars that are known to be less susceptible to the disease.
Practice good garden hygiene: Regularly clean up fallen leaves and plant debris around your boxwoods, as they can harbor the blight-causing pathogen. Dispose of the infected material properly to prevent further spread.
Monitor and inspect: Regularly inspect your boxwoods for any signs of disease. Early detection allows for prompt treatment and containment.
Sanitize tools and equipment: Disinfect pruning tools and other gardening equipment after use, especially if you have been working with infected boxwoods. This helps prevent accidental transmission.
Avoid overhead watering: Since water splashing is a common mode of transmission, try to avoid overhead watering on your boxwoods. Instead, use drip irrigation or soaker hoses to deliver water directly to the root zone.
Boxwood blight is a serious threat to boxwood plants and the overall health of your garden. By understanding what it is, how it spreads, and implementing preventive measures, you can protect your prized boxwoods from this devastating disease. Remember to stay vigilant, practice good garden hygiene, and consult with a professional if you suspect boxwood blight in your garden.

Protect your boxwoods and keep your garden thriving! Take action against boxwood blight today.