Selections for 2011
Oklahoma Proven is a plant promotion program coordinated by faculty in the Department of Horticulture and Landscape Architecture at Oklahoma State University. The goal of the program is to recommend plants well-adapted for use across Oklahoma.
Collector's Choice for 2011
Silver linden is a beautiful large shade tree that can grow50’ to 70’ tall. It is quite tolerant of high pH soils and urban conditions and is more heat tolerant than other lindens making it a great street or shade tree for large yards in Oklahoma. Leaves of silver linden are dark green on the upper surface and silvery beneath, providing an interesting effect when the wind blows; leaves can have a nice yellow fall color. Tiny, fragrant, white, flowers attract bees in late June to July. Cultivars selected for brilliant fall color as well as outstanding performance are available.
- Exposure: Full sun
- Soil: Prefers moist, well-drained soil; tolerant of high pH soils and pollution
- Hardiness: USDA Zone 4-7
Tree for 2011
American Elm Collection
New Harmony, Princeton, and Valley Forge
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 today. ‘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’ is also vase-shaped. American elms are adapted to a wide variety of soil conditions, tolerate deicing salts, air pollution, drought, and a range of soil pH. They have yellow fall color.
- Exposure: Full sun to part shade
- Soil: Prefers well-drained soil
- Hardiness: USDA Zone 5-9
Shrub for 2011
Kaleidoscope, Little Richard, and Rose Creek
Abelia x grandiflora
Several new, compact forms of glossy abelia are becoming very popular. ‘Kaleidoscope’ grows 2-3’ high and slightly wider. In spring leaves appear on bright red stems with lime green centers and bright yellow edges, but variegation does not scorch or burn in hot weather and in fall color deepens to shades of orange and fiery red. Soft pink flower buds open to white in late spring. ‘Little Richard’ is 3’x3’, evergreen, with vivid green leaves in summer, taking on a tangerine-pink color in fall; white flowers bloom from summer to first frost. ‘Rose Creek’ grows 2-3’ high and 3-4’ wide; is evergreen, with crimson stems. New leaves have a pinkish cast, maturing to lustrous dark green, and turn purple in cold weather. Small white flowers are surrounded by persistent rosy pink sepals. Use these abelias in containers, as formal or informal hedges, accent plants, in mass plantings, or in foundation plantings under windows. Abelias also attract hummingbirds and butterflies to the garden.
- Exposure: Sun to part shade
- Soil: Moist, well-drained, acidic
- Hardiness: USDA Zone 6-9, evergreen in 7 and warmer
Perennial for 2011
Giant coneflower is native to eastern Oklahoma, but does well throughout the state. It is tolerant of moist soils and is quite drought tolerant once established. Giant coneflower has silvery-blue foliage. Flowers have bright yellow ray flowers that dangle from a large, upright, dark brown cone on stems that reach 5-6 feet high. Giant coneflower blooms in early summer but deadheading the spent blossoms will encourage another flush of blooms in late summer. Plant in masses for best effect. Can be used in mixed borders, meadows, native gardens, and open woods. This species makes a strong vertical statement in the landscape.
- Exposure: Sun, part shade
- Soil: Moist, well-drained
- Hardiness: USDA Zone 4-8
Annual for 2011
Pink Crystals Ruby Grass
Melinus nerviglumis 'Savannah'
Pink Crystals Ruby Grass is a warm season grass that likes it hot and performs best in those conditions. Growing only 18 to 22” tall, it is an attractive ornamental grass with blue green foliage and ruby-pink blooms with glistening silky hairs in late spring. Flowers retain their color even when dried and may be used for cut flower arrangements. Pink Crystals Ruby Grass is excellent in beds, borders, and is spectacular in a container planting.
- Exposure: Full sun to part shade
- Soil: Well-drained
- Hardiness: Use as an annual