Oklahoma Proven selections are safe bet for gardeners
For the last few weeks, Oklahoma gardeners have probably been thinking more about snow removal and keeping their pipes from freezing than fertilizing the soil or pruning plants. But now that there is a break in the winter weather, gardening enthusiasts can start planning their landscapes for spring and summer.
For 13 years the Oklahoma Proven program has helped guide gardening enthusiasts toward plants, trees and shrubs that have been proven to grow well in Oklahoma's diverse climate and soil types.
The selections for 2011 promise to provide gardeners with lots of color and texture, said David Hillock, Oklahoma State University Cooperative Extension consumer horticulturist.
"Oklahoma Proven is a program designed to help gardening enthusiasts select annuals, perennials, trees and shrubs that will grow well across the state," Hillock said. "Each year we select a tree, shrub, perennial and annual that will help gardeners grow beautiful gardens and landscapes."
This year's selections include the American elm collection, which includes New Harmony, Princeton and Valley Forge; the abelia collection, including Kaleidoscope, Little Richard and Rose Creek; Giant Coneflower; and Pink Crystals Ruby Grass.
In addition to these four selections, Oklahoma Proven also offers the Silver Linden as the Collector's Choice selection this year. This is the third year for this category and is a recommendation made with adventuresome gardeners in mind.
"The Collector's Choice selection may need special placement or a little extra care, but it will be rewarding and impressive in the garden," he said. "The Silver Linden is a large shade tree that can grow up to 70 feet tall. It's tolerant of high pH soils and urban conditions. Because it's more heat tolerant than other lindens it's a great street tree and shade tree for large yards."
The leaves on this tree are dark green on the upper surface and silvery underneath, which provides an interesting visual effect when the wind blows; leaves turn yellow in the fall. Small yellow and white fragrant flowers attract bees in late June through July. This tree grows best in USDA Zones 4-7.
The abelia collection is the shrub selection for 2011. Kaleidoscope, Little Richard and Rose Creek are new, compact forms of the glossy abelia and are becoming quite popular.
Geared toward zones 6-9, abelias attract hummingbirds and butterflies to the garden. Kaleidoscope grows 2 to 3 feet high and slightly wider. In the spring, leaves appear on bright red stems with lime green centers and yellow edges.
"One great feature about this plant is that the variegation doesn't scorch or burn in hot weather," Hillock said. "In the fall the color deepens to shades of orange and fiery red."
Little Richard is evergreen with vivid green leaves turning deep green in summer with tangerine pink in cooler weather and white flowers bloom from summer to first frost. Rose Creek also is evergreen with crimson stems. When new leaves appear they have a pinkish cast. As the leaves mature they turn a lustrous dark green before turning purple in cold weather. These selections from the abelia collection grow well in sun to part shade in moist, well-drained, acidic soil.
This year's perennial is the Giant Coneflower. Although it is native to eastern Oklahoma, it grows well statewide. It is tolerant to moist soils, but once established is quite drought tolerant and grows in zones 4 to 8. The foliage is silvery-blue and the flowers have bright yellow ray flowers that dangle from a large, upright, dark brown cone on stems that reach 4 to 5 feet tall.
"The plant blooms in early summer but deadheading the spent blossoms will encourage another flush of blooms later in the summer," he said. "To maximize this flower, plant it in mass. Use it in borders, meadows, native gardens and open woods."
The 2011 annual is Pink Crystals Ruby Grass, which is a warm season grass that likes it hot and performs best in a very warm climate. It grows to about 18 to 22 inches tall and is an attractive ornamental grass with blue green foliage and ruby pink blooms with glistening silky hairs shimmering in late spring. The flowers retain color even when dried and can be used for cut flower arrangements. This selection is a great choice in beds and borders, as well as container plantings.
The final selection for Oklahoma Proven 2011 is the American elm collection. With the release of improved, disease resistant American elms, they are once again in demand.
Valley Forge, New Harmony and Princeton are a few of the cultivars available. Valley Forge is upright, arching, broadly vase-shaped with a full, dense canopy. New Harmony develops into a broad, vase-shaped crown with arching branches terminating in numerous slender, often drooping, branchlets. Princeton also is vase-shaped and is an older clone that proved to be very resistant to Dutch Elm Disease.
Gardening enthusiasts who wish to see full color photos of the 2011 Oklahoma Proven selections can go to www.oklahomaproven.org.
Oklahoma Proven is sponsored by the OSU Cooperative Extension Service; Oklahoma Agricultural Experiment Station; OSU Department of Horticulture and Landscape Architecture; Oklahoma Department of Agriculture, Food and Forestry; Oklahoma Greenhouse Growers Association; Oklahoma Botanical Garden and Arboretum; Oklahoma Nursery and Landscape Association; and Horticulture Technologies at OSU/OKC.