Oklahoma Proven Selections Are Safe Bet For Gardeners

By Trisha Gedon, Oklahoma State University

First posted on 03-11-2010

For a dozen years now, 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 2010 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 Indian Cherry, Koreanspice Viburnum, Toad Lily and Silver Falls Dichondra.

In addition to these four selections, Oklahoma Proven also offers the Caddo Sugar Maple as the “Collector’s Choice” selection. This was a new category last year 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 Caddo Sugar Maple is a native population of sugar maple found growing in Caddo County in southwestern Oklahoma. The leaves are dark green, deeply lobed and leathery, which makes it more resistant to leaf tatter and scorch.”

This tree is very tolerant of high pH soils, extreme heat and drought conditions that are common across much of the state. It can reach 30 feet to 50 feet tall and is a beautiful medium to large shade tree. In the fall the leaves can range from yellow to orange and sometimes red. It is recommended for USDA Zone 5-9.

Indian Cherry is the 2010 tree selection. It is a small tree or large, multi-stemmed shrub that grows up to 20 feet tall with a rounded to spreading canopy. The foliage is dark, lustrous green all summer, turning yellow to orange yellow in the fall.

“This tree’s greatest asset is the colorful fruits that develop in late summer to early fall, turning red and then to black as they mature,” he said. “As an added bonus, the fruit attracts several species of birds and can be used to make jams and jellies.”

Indian Cherry can be grown in full sun to shade, prefers well-drained soil and is recommended for USDA Zone 5-9.

The 2010 shrub selection is the Koreanspice Viburnum. It is a small to medium sized shrub offering year round interest. In the summer the leaves are dark green, turning to wine-red in the fall. Flower buds are pink to red and open to white or pink in the spring and the flowers omit a wonderful fragrance.

Hillock said once the shrub has become established it is very heat and drought tolerant, although it prefers moist, slightly acid soils, and sun to part shade.

“This shrub also is tolerant of high pH soils and fortunately, wind-swept conditions,” he said. “It grows 4 feet to 5 feet high and just as broad. A good use for this shrub is as a foundation planting or incorporated into a mixed border. It’s a wonderful selection for USDA Zone 5-7.”

Toad Lily is the 2010 Oklahoma Proven perennial selection. They are known for their unique flowers that feature pale lilac with dark purple spots that appear on upright arching stems in late summer to early fall.

“This is a great choice because many other plants are beginning to wind down and the Toad Lily will offer gardeners color later in the season,” Hillock said. “Because the flowers are small, be sure to place this plant in a spot where the flowers can be appreciated up close.”

Toad Lily is easy to grow, resistant to deer, somewhat drought tolerant, but grow best in moist soils. This plant also can tolerate wet conditions. Shade to partial shade is the best placement in USDA Zone 4-8.

The final selection for Oklahoma Proven 2010 is the Silver Falls Dichondra. This annual was selected for its very low growing, creeping, trailing habit and beautiful silvery gray leaves that resemble small lily pads.

“Silver Falls is actually a selection of a dichondra species native to southwest Texas and Mexico so it’s quite heat and drought tolerant, two conditions we experience in Oklahoma,” Hillock said.

Silver Falls grows only 2 inches tall and 3feet to 4 feet wide and serves as an attractive ground cover. Another option is to use it in a container planting or hanging basket where the vines can spill over.

Gardening enthusiasts who wish to see full color photos of the 2010 Oklahoma Proven selections can go to http://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.