'Okahoma Proven': New selections kick off 20th anniversary of landscape program
It is not always easy to decide what plants to use in your garden and landscape, especially if you have limited space, but the Oklahoma State University "Oklahoma Proven" program, in its 20th year, is designed to help you do just that.
Each year since 1999, a tree, shrub, perennial and annual worthy of state landscapes are chosen by horticulturists to help consumers choose plants appropriate for Oklahoma gardens. The Oklahoma Proven selections for 2019 have just been announced.
The tree selected for 2019 is Pinus flexilis "Vanderwolf’s Pyramid" Limber Pine. It's an evergreen with a pyramidal habit that typically grows 20 to 30 feet tall and about 10 to 15 feet wide. The specific epithet and common name is in reference to the flexible (limber) branchlets/twigs. This pine is noted for its closely spaced, twisted, silvery blue-green needles.
Limber Pine is native to North America and generally considered to be an adaptable, low-maintenance tree with few problems, including resistance to pine wilt disease. This tree prefers full sun exposure and a moist, well-drained soil.
The Oklahoma Proven shrub selected for 2019 is actually a series of double-flowering quince (Chaenomeles speciosa) called the Double Take series. The shrubs are hardy, deciduous shrubs reaching 4 to 5 feet high and at least as wide. They produce a profusion of early spring double flowers that resemble camellias. This is a dense, broad-rounded, shrub, and unlike many quince, they are thornless.
The bold double flowers (up to 2 inches in diameter) of the Double Take series bloom before the leaves fully unfold in an early spring and come in colors of scarlet, orange, pink and peach. The plants do not produce fruit. Oval to oblong, glossy dark green leaves provide an attractive look through the summer. They should be pruned lightly after blooming in spring when needed.
Double Take flowering quince will take full sun to part shade and are drought tolerant once established. They tolerate a wide variety of soils, but prefer well-drained. They are winter hardy in Oklahoma.
The 2019 Oklahoma Proven selected perennial has a great name that fits it well. Rattlesnake Master, Eryngium yuccifolium, is a native species to the tall grass prairies. Leaves of Rattlesnake Master are parallel-veined, bristly edged, sword-shaped and medium green (up to 3 inches long) resembling those of yucca. Flowers are greenish-white and tightly packed into globular, 1-inch-diameter heads resembling thistles.
Rattlesnake Master prefers dry, sandy soils, but tolerates clay and shallow-rocky soils. Plants tend to open up and flop in overly fertile soils or in anything less than full sun. This is a taprooted plant that transplants poorly and is best left undisturbed once established.
Use Rattlesnake Master in a xeriscape garden, perennial border or native garden. Group plants in naturalized areas for best affect. This perennial will grow in sun or part shade and prefers well-drained soils but can take moist or dry conditions.
Rattlesnake Master is hardy in the U.S. Department of Agriculture Hardiness Zones 5-9, so it is a great selection for Oklahoma gardeners.
The 2019 Oklahoma Proven annual flower is the starflower, Pentas lanceolata Graffiti series. This series thrives in very and dry conditions. Considered to be the most uniform Starflower in habit, as well as bloom time, Graffiti grows to 16 inches high and 12 to 14 inches wide making it a great plant for containers or in a flower bed.
Graffiti comes in several colors — red, rose, pink, white, violet and lavender. Graffiti plants are heat- and drought-resistant and make great cut flowers. Pollinators are attracted to the tightly clustered flowers that sit above the foliage all summer long.
Like all Starflowers, Graffiti prefers soil that is not too rich; if it's a bit on the dry side, all the better. Heat, sun and good drainage will have the plants blooming heartily all summer long.
As you begin your gardening and landscaping season this spring, consider Oklahoma Proven selections. To see all the plants recommended by the Oklahoma Proven Plant Selection Program for the past 20 years, go to the newly updated web site, www.oklahomaproven.org/.