Selections for 2016
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 2016
MagnoliaDeciduous forms of magnolia are spectacular additions to any spring landscape. Among the most popular of deciduous forms are star magnolia (M. stellata) and saucer magnolia (M. x soulangiana), but several others are available along with their many hybrids, which provide a wide variety of flower colors from red to white, yellow, pink, or purple. The most common color available is pink, but others should be tried such as ‘Elizabeth’, an older selection with creamy yellow flowers, or ‘Butterflies’, a newer selection with deep yellow flowers. Flowers of deciduous magnolias appear just before or while the leaves are emerging in spring. Early flowering varieties can be damaged by late frosts; avoid placing plants in a southern exposure where flowers will open early. Deciduous magnolias can range in size from small to medium shrubs to large trees.
- Exposure: Full sun to part shade
- Soil: Prefers moist, well-drained, acid soil, but is adaptable
- Hardiness: USDA Zone 4-9
Tree for 2016
Escarpment Live Oak
Escarpment live oak is a smaller version of the coastal live oak (Q. virginiana) growing slowly to 20 to 40 feet high and about as wide with picturesquely gnarled branches and evergreen leaves. Escarpment live oak is native to southern Oklahoma through central and western Texas to northern Mexico, which means it is also more drought and cold tolerant than coastal live oak. Because of its slower growth it is a perfect long-lived shade tree for smaller, urban landscapes. Branches provide excellent nesting sites for birds and small mammals. Acorns are elongated and eaten by wildlife. It is also the larval host of the Hairstreak and Horace’s Duskywing butterflies.
- Exposure: Full sun or light shade
- Soil: Alkaline to slightly acid, well-drained soils
- Hardiness: USDA Zone 6-10
Shrub for 2016
Color Guard Variegated Yucca
Yucca filamentosa 'Color Guard'
Yucca is virtually a stemless evergreen shrub native to the southeast. ‘Color Guard’ is a gold-centered, variegated form with upright sword-shaped leaves that provide striking architectural features to the garden. Flowering stalks arise in late spring from the center of the plant bearing long, terminal panicles of bell-shaped, nodding, fragrant, creamy white flowers. ‘Color Guard’ yucca is free of pests and is tolerant of dry areas. It is excellent in borders, xeriscape plantings, containers, and as an accent plant.
- Exposure: Sun to part shade
- Soil: Dry to medium, well-drained soil
- Hardiness: USDA Zone 3-8.
Perennial for 2016
Sedges belong to the genus Carex, which is a genus of many species, most from wet areas such as bogs. Sedges have triangular, grass-like stems and panicles of short flower spikes. Foliage can be evergreen or deciduous and colors range from green, brown/rust, golden, blue, to variegated. Sedges are grown in groups or masses, as a lawn substitute, in naturalized areas, perennial borders, and habitat restoration. They are grown particularly in shady areas where the variegated varieties really shine. Some require damp or wet conditions while others are relatively drought tolerant.
- Exposure: Full sun to part or full shade
- Soil: Dry to wet soils
- Hardiness: USDA Zone 3-10
Annual for 2016
Annual Vinca (improved, resistant varieties)
Annual vinca, also goes by Madagascar periwinkle and other common names, tolerates the heat and humidity of the southeast. Full sun and warm soil temperature is required for this species to thrive and it is tolerant of low fertility soils and is drought tolerant. Flower colors come in shades of white, pink, red, and purple. Plants grow 6 to 12 inches tall and 8 to 24 inches wide depending on cultivar. Improved cultivars provide an abundance of flowers on stocky plants and disease resistance, which is very important with this species. Improved cultivars include plants in the Cora series, Mediterranean series, Titan series, and many others.
- Exposure: Full sun to part shade
- Soil: Well-drained, slightly dry soil
- Hardiness: Use as an annual