It’s time for boxwood-loving gardeners to learn the abbreviation B.M.P. — best management practices — and get with the program. Boxwood needs our informed attention and care to do its job as the indispensable landscape element it has become since the first Buxus were planted in the United States in the mid-17th century.
It is hard to think of another plant that lends such year-round structure to a design as boxwood, defining spaces with its evergreen presence, while holding little interest for hungry deer — another big plus.
But in the last decade or so, the fungal pathogen Calonectria pseudonaviculata, which causes boxwood blight, has tarnished this garden mainstay and important nursery crop. The disease — first identified in the United States in 2011 and recorded in at least 30 states and the District of Columbia since then — has triggered a surge of research into how to control it, and into the possibility of breeding resistance into boxwood genetics.
AJF Design, the challenge underscores a feeling she was having years before the arrival of the disease. The conventional wisdom of boxwood maintenance — starting with regular, drastic shearing to within an inch of the plant’s life — didn’t seem to her to match boxwood’s needs.
“This plant, historically, has been mistreated,” said Ms. Filippone, who in March became president of the American Boxwood Society, an organization of enthusiasts, from nursery professionals to home growers. “We baby this plant to death. Plants are overwatered, over-fertilized and allowed only a little crust of leaves to photosynthesize with.”
Saunders Brothers, called “a new mind-set of the boxwood gardener.” His Virginia-based family business, a wholesale nursery that is more than a century old, has made boxwood its “signature crop” since around 1950, he said. Today, that means focusing on breeding for more resilience against blight and boxwood leafminer, an insect pest.
Saunders Brothers has been actively selecting among cultivars for blight resistance since 2011, when the nursery had about 150 varieties in its collection to evaluate. The gardeners there began making crosses of the more resistant varieties, and now the resulting 5,000 unique seedlings need to be screened for disease and pest resistance. The process continues, but two cultivars have been introduced so far: NewGen Independence and NewGen Freedom.