Big Changes on the Horizon for Woody Ornamentals
The next few years are going to be exciting for woody ornamentals growers, with big changes ahead, such as better breeding for disease and weather resistance, noninvasiveness, and drought tolerance, plus bigger, better, longer-lasting blooms.
“Soon consumers can look forward to multi-colored redbuds, syringa with much lower chill requirements, a wide range of new Hydrangea macrophylla flower forms, and cold-hardy gardenias, and lots will be happening with viburnum, too,” says Pete Kruger, Star Roses and Plants Director of Product Development and Licensing.
Star Roses & Plants’ Lagerstroemia Bellini Series exhibits good cold tolerance in Zones 6 to 10 and blooms the first year in a container, exhibiting a compact, rounded habit. Plants are resistant to powdery mildew, and they will rebloom after trimming. New this year is Lagerstroemia ‘Bellini Raspberry.’ Also new is Calycanthus ‘Burgundy Spice,’ the first calycanthus on the market completely covered with purple foliage. It tolerates a wide range of growing conditions and is deer resistant.
More Noninvasive Options Available and in the Pipeline
Kruger says he feels that invasiveness and drought tolerance will be two of the biggest concerns breeders will continue to focus on for woody ornamentals.
Developing noninvasive varieties is certainly at the top of Spring Meadow Nursery’s list. The nursery has introduced other non-invasive varieties in the past, such as ‘Lo & Behold’ butterfly bush, ‘Golden Ticket’ privet, and multiple roses of Sharon. After years of development, it is introducing two new sterile barberries ─ ‘Sunjoy Mini Maroon’ with 0 to 1.2% seed viability and ‘Sunjoy Todo, which produces no seed. Both varieties offer rich, season-long color, compact habits, and disease and deer resistance, but they eliminate the threat of spreading.
Another good example of breeding to solve the issue of invasiveness is the nandinas from the Southern Living Plant and Sunset Western Garden collections. These plants rarely bloom and some varieties do not bloom at all, and they have little to no viable seed. Ligustrum ‘Sunshine’ is another non-invasive cultivar that won’t reseed in the landscape, and it doesn’t produce clouds of white, sneeze-producing blooms.
Disease-Resistant Alternatives Address Boxwood Blight
Consumers also want low-maintenance shrubs that are disease-resistant and that tolerant tough weather conditions. Monrovia has introduced the Grace and Grit rose collection for 2018 that stands up to black spot, heat, and humidity. For people in the North, it is offering new spireas with improved cold tolerance, and for the Southwest regions, an upright Prunus ‘Bright ‘n Tight’ with showy flowers and year-round interest. Additionally, it is looking into some buxus varieties for the future that show resistance to boxwood blight, a fungal disease that has plagued the nursery industry since 2011.
In addition to finding varieties that are resistant to boxwood blight, breeders such as Spring Meadow Nursery also make it a priority to provide alternatives.
“The threat of boxwood blight has led to the release of ‘Gem Box’ inkberry holly. It acts in much the same way as a boxwood, but isn’t susceptible,” says Shannon Downey, Public Relations and Marketing Specialist for Spring Meadow Nursery. “Several more alternatives are being released in the future, such as ‘Strongbox’ inkberry holly and Pyracomeles ‘Juke Box’ for the south.
New Varieties Deliver More Bloom for the Buck
The trend toward breeding for bigger blooms, earlier blooms, and extended blooming periods continues, but now consumers want something more.
“Instead of more bang for the buck, consumers want more bloom for the buck,” says Kip McConnell, Director of Plant Development Services, which is associated with the Encore Azaleas, Southern Living and Sunset Western Plant Collection brands.
The Southgate Rhododendron series from the Southern Living Plant Collection not only has an extended bloom time, it also thrives in the Deep South and reduces or eliminates common root issues that traditional rhododendrons suffer from in the South. The Encore Azalea collection also has a long bloom season. Azaleas in this collection can bloom eight months of the year in some parts of the country.
Endless Summer hydrangeas from Bailey Nurseries can be prolific re-bloomers. The original Endless Summer variety was one of the first hydrangea discovered that blooms on the previous year’s wood stems and new-season growth. Bailey recently announced at its annual consumer expo that Endless Summer was named as the official flower of the Super Bowl in 2018. Bailey also introduced its newest hydrangea at the expo – ‘Berry White’ – a paniculata type in its First Editions line with thick upright stems and large panicles that hold up in wind and rain. The red pigment in the sepals on this variety exhibits much earlier in the growing season than its popular cousin, ‘Strawberry Sundae.’
Marc McCormack, Director of Sales and Marketing at Bailey Nurseries, says an additional new macrophylla variety is in the works that will be a gamechanger for the industry in terms of color in the garden, as well as the container.
“We are also working as a company and with other breeders on specific genera like hydrangea and other species where we are doing ploidy work to try to increase leaf thickness, stem size, flower size and or sepal size, and re-blooming capabilities,” McCormack says. “It’s a process that takes time and patience.”