Oklahoma Proven Selections for 2019

Oklahoma Proven Selections for 2019

Allen Robinson: Ask a Master Gardener

Sunday, March 17, 2019

Q: Given our erratic weather patterns, is there a good way to know what plants, trees and shrubs grow well in our area? Sam R., Tulsa

Rattlesnake Master
MG Demo Garden

A: This is a good question that many people think about. And it’s a very reasonable request given the amount of labor involved in planting, as well as the cost of landscaping products these days. So wouldn’t it be nice if someone had already done the research on which plants do best in our neck of the woods? And also tell us where to plant them so they have the highest chance of success? Well, they have!

It’s called the Oklahoma Proven Program. Oklahoma Proven is an annual plant evaluation and marketing program coordinated by the Department of Horticulture and Landscape Architecture at Oklahoma State University. Designed to help consumers select the best plants for Oklahoma gardens, these plants are tolerant of the varied and difficult environmental conditions found throughout Oklahoma.

Every year, an annual, a perennial, a shrub and a tree are selected. The selections for 2019 are:

Annual: Star Flower (Graffiti® series) grows to 16 inches high and 12 inches wide, making it a great plant for containers or in a flower bed. They are very heat-tolerant, drought-resistant, make great cut-flowers and attract butterflies and hummingbirds throughout the summer months. Like all Pentas, Graffiti® prefers sun/heat, dry soil with good drainage but not too rich.

Perennial: Rattlesnake Master is a native species to the tallgrass prairies. Leaves are parallel-veined, bristly-edged and sword-shaped, with medium green leaves (up to 3 feet long) resembling those of yucca. Flowers are greenish-white and tightly packed into globular, 1-inch diameter heads resembling thistles. It prefers dry, sandy soils and is best left undisturbed once established. Perfect for a xeriscape garden, perennial border or native garden. Group plants in naturalized areas for the best effect.

Shrub: Flowering Quince (Double Take™ series) are hardy, deciduous shrubs reaching 4 to 5 feet high and as wide. It produces a profusion of early spring double flowers that resemble camellias. A thorn-less shrub with bold 2-inch double flowers, it comes in colors of scarlet, orange, pink and peach. Does not produce fruit. Very drought tolerant. If needed, prune lightly after it blooms in spring.

Tree: Limber Pine (“Vanderwolf’s Pyramid”) is an evergreen tree with a pyramidal habit that typically grows 2 to 30 feet tall and 10 to 15 feet wide. It is noted for its closely spaced, twisted, silvery blue-green needles. Being native to North America, it is an adaptable, low-maintenance tree with few problems, including being resistant to pine wilt disease.

Note: All of these plants do well in the Tulsa metropolitan area whose USDA Hardiness Zone is 7A (average low temperature of 0 to 5 degrees).

The Oklahoma Proven program has been in existence since 1999. The best part is that you can find every year’s selection back to 1999 online at oklahomaproven.org.

Remember that all plants need special attention during the establishment phase or during periods of environmental extremes. So be sure to give them some TLC until they get established. Then, watch them succeed!

While nothing in nature is guaranteed, you can significantly improve your odds by choosing Oklahoma Proven varieties.

Garden tips

• Remove flowers from spring-blooming bulbs after blooming is completed. This will allow the plant to direct its energy into its bulb for next year's blooms, rather than producing seeds. But allow foliage of these bulb plants to die and turn brown naturally before removal. As long as the leaves are green, they are storing energy for the following year. Fertilize them at the time of planting, in the fall or in the spring when their leaves first emerge.

• Cool-season lawns, such as bluegrass, fescue and ryegrass, may be fertilized now with the first application of the season. Usually, four applications of fertilizer are required per year in March, May, October and November. Never fertilize these lawn grasses in summer.

• Start your routine fruit tree spray schedule prior to bud break. Contact the Master Gardener office for a document outlining recommendations for all fruit tree types as they are not all the same.