Stop boxwood blight from ruining your garden with these tips.
Matthew Benson
Boxwood is a popular feature in many gardens,especially in hedges.
What Is Boxwood Blight?
Credit:Matthew Benson
Boxwood blight is a plant disease that affects all types ofboxwood plants(Buxusspp.).
Two fungi cause it:Calonectria pseudonaviculataandCalonectria henricotiae.
The disease was initially found in the United Kingdom in 1994.
It was identified in both North Carolina and Connecticut in 2011.
In many parts of the country, these conditions last for several months of the year.
The fungal spores are heavy, sticky, and not spread by wind.
However, strong winds orleaf blowers can throwinfected leaves onto otherwise healthy plants.
Leaf spots start as small dark dots and grow up to about 1/3 inch wide.
The inside becomes tan-colored and surrounded by a ring of dead black leaf tissue.
You may notice a red, orange, or yellow halo surrounding the leaf spot.
Asleaves become infected, they fall off the plant, leaving bare stems.
Leaf drop can occur quickly.
Heavily affected plants can shed their leaves within a week.
Unhealthy-looking boxwood might be unrelated to a disease.
It is essential to confirm the diagnosis before beginning a treatment plan.
Is There a Boxwood Blight Treatment?
No treatments are currently known to cure plants infected with boxwood blight.
However, fungicides are effective at helping prevent the disease in otherwise healthy plants.
Rotating sprays is vital to prevent the boxwood blight from developing resistance to any one particular chemical.
Avoid contact with your plants while waiting for the results.
The boxwood blight fungus can survive in the soil and leaf litter for five or more years.
Simply removing an infected plant may not be enough to eradicate the disease spores from your garden.
Should I Still Plant Boxwood in My Garden?
Plant breeders are working hard to develop boxwood varieties that are resistant to blight.
Two notable introductions are NewGen Boxwood and Better Boxwood.
These collections include multiple cultivars to suit different needs in the garden.
Consider avoiding installing these plants around your boxwood in the future.
What Next?
Researchers and plant breeders are actively working on the problem of boxwood blight.
