There’s a saying that the only two things a person can count on is death and taxes. Fortunately for gardeners in Oklahoma, they can also count on the Oklahoma Proven selections for successful gardening.

 

Oklahoma Proven is a plant promotion program to help guide gardeners toward appropriate garden selections that have been proven to grow well in Oklahoma’s diverse climate and soil types.

 

The program began in 1999 with recommendations for a tree, shrub, perennial and annual worthy of Oklahoma landscapes. Now in its 23rd year, the 2022 selections include: tree – Ginkgo biloba (Maidenhair tree); shrub – Cephalanthus occidentalis (Buttonbush); perennial – Heuchera cultivars (Coral Bells or Alum Root); and annual – Plectranthus scuteleroides (Coleus). This year’s selections also include the Collector’s Choice, which is the Ungnadia speciosa (Mexican buckeye). While it does grow well in Oklahoma, the Collector’s Choice is for the adventuresome gardener and may require special placement or extra care.

 

The Ginkgo biloba tree is unique in that there’s only one species of the genus. Something else you may notice is the leaves have two distinctive lobes that are somewhat leathery, fan-shaped and have almost parallel veins. Ginkgo trees reach about 50 to 80 feet high and 30 to 40 feet wide in ideal conditions. Keep in mind they are slow growers, and it takes decades for them to reach mature height. This is a great selection for an urban environment because of its tolerance to compacted soils, heat and air pollution.

 

Buttonbush is a native shrub found growing along streams and lakes across most of Oklahoma, excluding the panhandle. It typically grows about 5 to 8 feet tall and 4 to 8 feet wide. If you like hummingbirds, the flowers on the buttonbush are attractive to these fast-flying birds. Bees, butterflies and other pollinators also like this shrub, which is tolerant to heat and soil compaction, but doesn’t like very dry soil. It’s a great selection for a rain garden, pollinator garden or a native garden.

 

Coral bells love the sun but need to be planted in an area protected from late afternoon sun. The light-colored foliage varieties do best in the shade, while dark-colored foliage forms will tolerate more sun. Although drought tolerant once established, this perennial will need watering during dry spells due to its shallow root system. Coral bells may need to be divided periodically to keep them vigorous and healthy. Add a light layer of mulch around the plant in the winter to protect the roots from freezing.

 

Coleus is a time-honored plant that is quite diverse and full of character. It features great foliage colors, patterns and forms and is known as a great colorful plant for shade or as a house plant.

 

However, many cultivars are now full sun tolerant, which makes them a great addition to the landscape. Too much shade will make the plant leggy. Keep the soil moist. Coleus cultivars range in size from dwarf, 6-inch plants to a large, 36-inch mound. It’s a great selection for a border, hanging basket or container. If grown indoors, keep it near a window for bright light.

 

The Mexican buckeye is a great choice for the adventurous gardener. This multi-stemmed large shrub or small tree reaches 15 to 30 feet tall and about 20 feet wide. Native to west/central Texas, Mexico and New Mexico, its fragrant pink flowers bloom as it leafs out. It can be used as a multi-trunk shrub or trained into a small tree. It is very drought tolerant and actually prefers dry areas making it a great selection for central and western Oklahoma.

 

All of the previous years’ selections, as well as more information about the 2022 selections, is available online at Oklahoma Proven.