We all know the Flower Show is a great place to learn about plants and flowers. Coming to the Show this year is a special display and workshop about PHS’s Gold Medal Plants, which are chosen for their superb eye-appeal, performance and hardiness in the growing region of Zones 5-7, and for their beauty in many seasons, whether it be their foliage, flower or structural form.
Here is a list of the five outstanding woody plants as the 2010 winners of the Gold Medal Plant Awards. They were announced by Joe Ziccardi Jr., coordinator of the PHS Gold Medal Program, at the Woody Plant Conference held July 17 at Swarthmore College.
Clethra alnifolia ‘Compacta’ (Dwarf Summersweet)
In the mid-1970s Tom Dilatush, a noted nurseryman and longtime PHS Gold Medal committee member, discovered Clethra alnifolia ‘Compacta’ growing on a New Jersey compost pile. Tom was impressed by the specimen’s superior landscape characteristics, and his keen observation was reaffirmed 30 years later by the high marks the plant received as ‘Tom’s Compact’ (the plant’s original name, which is sometimes still used) in Longwood Garden’s shrub trials. ‘Compacta’ is a superior variety of summersweet, displaying darker, glossier leaves and a more compact, denser growth habit than other cultivars. This “mulch-mound-miracle” is also hardier and more floriferous than its competition. What else could you ask for? Oh, yes, it’s also native, low-maintenance, and moderately deer-resistant. Uses include the foundation, border, in mass, the shady container, and the naturalized garden. It is best planted in part sun, but it tolerates all light conditions. ‘Compacta’ grows about 3 ½ feet high by 4 feet wide and prefers well-drained organic soil. Hardy in Zones 4 to 9.
Ilex Red Beauty® (Red Beauty Holly)
As the name implies, this holly bursts into an eye-catching sensation when its berries ripen in autumn, far outperforming other evergreen hollies. Handsome dark glossy evergreen leaves create a densely branched pyramidal tree. Introduced by Elwin R. Orton at Rutgers, Red Beauty® is a result of years of specialized cross-breeding between Ilex aquifolium, Ilex rugosa, and Ilex pernyi. Essentially, it’s half Meserve (blue) holly and half Perny holly. For berry production, Red Beauty® needs a male pollinator; use any of the blue male hollies such as Ilex ‘Blue Boy’, ‘Blue Prince’, or ‘Blue Stallion’ and plant one or two within 100 feet. (When selecting a site for the males, remember that they don’t produce berries.) Plant Red Beauty® in sun to part-sun in well-drained acidic soil. It is best used as a specimen tree or as a well-placed accent plant. It grows to about 15 feet high and is hardy in Zones 6 to 9.
Illicium floridanum ‘Halley’s Comet’ (Florida Anise)
Do you need a head-high evergreen for that shady spot? Look no further. Illicium floridanum ‘Halley’s Comet’ can fill this niche. A deer-proof shrub native to the southeastern United States, Florida anise produces 4-inch-long dark green leaves (similar to rhododendron), which emit a strong, pleasant fragrance when bruised. Outperforming the species and other cultivars, ‘Halley’s Comet’ has superior characteristics, including improved cold tolerance and faster growth. It’s also a better bloomer, with plenty of large, red, star-shaped flowers that bloom in May and can persist into the summer. It thrives in shady, moist, well-drained soil and tolerates part-shade; too much sun, though, will cause it to turn yellowish. Hardy in Zones 6 to 9. Adds Steve Mostardi of Mostardi Nursery in Newtown Square, PA, and chairman of the Gold Medal Committee: “Another great attribute of this plant is its ability to be tolerant of dry shade once it becomes established in the landscape.”
Juniperus conferta ‘Silver Mist’ (Shore Juniper)
A shortage of low-growing evergreens on the Gold Medal Plant list led to a search resulting in the selection of Juniperus conferta ‘Silver Mist’, a unique species within a common genus. The shore juniper, as it’s commonly called, is salt-tolerant and well-adapted for the seashore garden. The committee selected this urban-tolerant evergreen for its dense, more compact growth habit; exceptional bright silvery-blue needles; and robust, versatile demeanor. It is hardy in Zones 5b to 9. Gold Medal Committee member Barry Yinger found it in a small Japanese nursery and introduced it through Brookside Gardens in Wheaton, Md. He notes, “This distinctive form of the Japanese shore juniper has fluffy bright silver needles on a spreading plant that usually is less than a foot tall. It is extremely tolerant of heat and drought and is best used in a bright, sunny location with excellent drainage. If planted 2 to 3 feet apart, it will make an unusual ground cover that is beautiful all year around.”
Styrax japonicus ‘Sohuksan’ (Emerald Pagoda Snowbell)
Barry Yinger explains the history of this interesting plant: “In 1985, a group of plant explorers organized by the U.S. National Arboretum visited some remote islands off the southwest coast of South Korea. On Sohuksan Island, the group collected a distinctive form of the Japanese snowbell with a superior plant habit, large, glossy leaves, and very large fruit. Thanks to the horticultural wizardry of the late Dr. J.C. Raulston, a cutting he carried back to the North Carolina State Arboretum survived and established this tree in cultivation. Its larger glossy leaves are sun-tolerant, and its large white flowers are highly fragrant. It naturally makes a single-stemmed, medium-size tree attaining about 30 feet in cultivation, growing very fast in its first years and then more slowly. It grows best in fertile, well-drained soil in light shade with morning sun. It is sun-tolerant, but should not be planted in a hot, dry location.” Hardy in Zones 5 to 8.
Since 1979, the Gold Medal program has recognized plants of outstanding merit, though often undernoted and underused. When home gardeners acquire a Gold Medal winner, they can be assured the plant will exhibit standards of excellence for hardiness, disease and pest resistance, and ease of growing when planted and maintained as recommended.
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