The boxwood blight that is wiping out generations-old plants across the southeast hit Wake Forest University’s Reynolda Gardens in the fall of 2018, prompting experts to connect with Spring Meadow Nursery, to identify a boxwood replacement that is both consistent with the historic landscape and resistant to disease.
Boxwood blight is a serious and highly contagious disease caused by the fungus Calonectria pseudonaviculatum. It first appeared in the United Kingdom in the 1990s and in 2011 was detected in Connecticut and North Carolina. Since then, blight has been found in Alabama, Delaware, Florida, Georgia, Kentucky, Kansas, Massachusetts, Maryland, Missouri, New Jersey, New York, Ohio, Pennsylvania, Oregon, Tennessee, Virginia, West Virginia and Michigan.
Boxwoods have long been a critical design feature of the Reynolda landscape, framing the forecourt of south façade of the bungalow since 1937. The boxwoods in landscape architect Thomas Sears’s original plans were English dwarf boxwoods; however, this species was problematic and was replanted several times without success. Then, in 2015 as part of its landscape restoration project, Reynolda replanted the forecourt with Justin Brouwers boxwood, also called Korean dwarf boxwood and affectionately known as the “baby boxwoods” among the Reynolda staff.
Jon Roethling, director of Reynolda Gardens, said his staff first noticed discoloration in the boxwoods along the perimeter of the forecourt garden in early fall, 2018. The discoloration was soon diagnosed as blight infection. Shortly after diagnosing the boxwoods, Reynolda removed all infected boxwoods and treated all plants in close proximity to prevent fungal spread. At that time, 80 of the 300 boxwoods in front of Reynolda House were removed.
“Reynolda was not alone in seeing boxwood blight affect our plantings this fall,” says Karl Erik, director of operations at Reynolda House. “Landscapes in our surrounding neighborhoods and beyond also suffered. But here at Reynolda, addressing changes in our historic landscape is a particularly sensitive task that we approach with caution, and in consultation with experts in the field.”
Erik and Roethling talked with historic garden specialists, researched how other sites were dealing with the blight and ultimately connected with Tim Wood, the product development manager at Spring Meadow Nursery in Grand Haven, Mich. Wood agreed to provide Reynolda with a recommended replacement for the boxwoods, Proven Winners ColorChoice Gem Box Ilex glabra (inkberry holly). Ilex is proving to be a successful boxwood alternative in Europe, and Wood hopes Reynolda might become a case study for boxwood replacements in North American historic landscapes.
“Boxwood blight has been devastating in Europe,” Wood says. “We have been testing alternatives in France where huge numbers of boxwood plants were used in palace, castle and chateaux gardens as low hedges, called parterres. In addition to Gem Box we’ve been growing Strongbox, Sky Box, Patti-O Box Ilex, as well as Juke Box, a new thornless, nonflowering Pyracantha hybrid.”
All are recommended boxwood replacement cultivars and can serve different purposes in the landscape, with varying habits and features.
“There is a long history of this landscape being progressive and adapting to change,” says Roethling. “The decisions we make today about how to address this epidemic puts Reynolda at the forefront of demonstrating approaches for responding to our changing environment.”
Roethling and team favored Gem Box inkberry holly for its compact, rounded habit and small, dark green leaves that develop attractive red tips during the spring. Like boxwood, it responds well to pruning and can be sheared in globes or hedges with round or squared off edges. Unlike many generic versions of the species, it retains its lower foliage as it ages, making it an excellent replacement for boxwood. Inkberry holly is native to the Piedmont Triad and, according to Roethling, is a fitting replacement for the design of Reynolda’s forecourt.
“Our responsibility is to both maintain the integrity of the original landscape design and character, and respond to the changing needs of our environment,” Roethling said. “We’ll be watching these new plants closely and sharing information with the nursery and our colleagues working in other historic landscape and gardens.”