Wouldn’t it be great if there was a place that would test plants to see if they did well in our area and then let us know what they found? It would, and there is; the Oklahoma Proven Program from Oklahoma State University.

Each year, horticulturalists from OSU have a variety of plants in their test gardens. Some of these are new varieties and some are maybe varieties that don’t get much notice. Not everything in the test gardens makes the cut. Each year several plants are chosen, including a tree, a shrub, an annual, a perennial, and a plant for a new category called Collector’s Choice. Let’s talk about this year’s selections.

This year’s tree is the redbud. Granted, redbuds are not new to Oklahoma, in fact the eastern redbud (Cercis canadensis) is the Oklahoma State Tree but there are a good variety of redbuds out there for you to choose from.

Redbuds are found throughout North American and in some parts of Europe and Asia. It is a nice small to medium sized tree that typically grows to be about 20 to 30 feet tall. The first thing we notice about our redbuds is the bright purple flowers that pop out in the spring. Those are always a showstopper.

They prefer to be planted in well-drained soil and have average moisture requirements. While it doesn’t have to be planted in the shadow of a larger tree, they seem to do best in Oklahoma as an under-story tree.

While there are a variety of cultivars, you might consider the Mexican redbud, the Chinese redbud, or one called the Rising Sun Redbud. The striking thing about the Rising Sun is that the color of the leaves varies as you move from the trunk to the tip of the branch, changing from dark green to light yellow and orange. Either way, they are great trees for the appropriate spot in your landscape.

Next up is this year’s shrub known as the Harry Lauder’s Walkingstick. Interesting name…right? Maybe you know it by its other name - Contorted Filbert. Either way, this shrub is known for its unique curly, twisty stems, and foliage. The Walkingstick is a round, multi-trunked shrub that can grow to between 8 and 10 feet tall. There are also dwarf varieties that work great in small spaces or even containers.

The most interesting thing about this shrub is the contorted way in which the branches grow. During the growing season, the leaves can obscure the branches, but when winter arrives, you are left with a bare shrub that will always be a conversation piece. In addition, during the late winter, this shrub produces very small flowers with red stigmas and yellow grey catkins.

The Walkingstick prefers full sun to part shade in average garden soil but doesn’t do well in heavy clay soils. If you are looking for something unique in your garden, consider the Harry Lauder’s Walkingstick.

This year’s perennial is narrowleaf ironweed. These plants can be found in rocky terrain as well as floodplains primarily in west-central Arkansas and bordering Oklahoma counties. These plants can grow to be about two feet in height and width, doing best in dry to medium moisture soil. They have thin, narrow, highly textured leaves with bright purple flowers that bloom from mid to late summer. Once these flowers appear, they are very attractive to hummingbirds and butterflies. As a native plant, they tolerate heat and poor soil conditions. So, if you are looking for an interesting perennial that is built to handle our hot summers, take a look and the narrowleaf ironweed.

This year’s annual is the Profusion Red Yellow Bicolor Zinnia. Zinnias are a standard Oklahoma garden plant. This one was the winner of the Fleuroselect Gold Medal award in European performance trials as well. The flowers on this particular zinnia have an intense red center ring that is surrounded by golden-yellow outer petals. As they age, they gradually transition to shades of apricot, salmon, and dusty rose making the flowers interesting from start to finish. They are also great flowers for pollinators. Plant these zinnias in full sun to part shade in moist, well-drained soil.

We have several varieties of zinnias in our annual Online Plant Sale/Fundraiser including some from the Profusion series. Just go to www.tulsamastergardeners.org to shop.

The first selection for this new category of Collector’s Choice is the pawpaw. A lot of you right now are saying…wait… a pawpaw is a real thing? Yes they are and they produce very unique fruits as well. In the late summer to early fall, this tree will produce fruits that are sweet, with a custard like consistency.

Pawpaws are a native tree that will thrive in not only deep shade but also full sun. It can tolerate occasional wet conditions but will do best in well-drained, slightly acidic soil.

This tree produces purple-brown flowers that have both male and female flower parts. However, it is not self-fertilizing. If you are interested in the fruits, you will need to plant at least two different varieties of pawpaws. In addition, pawpaws attract butterflies and other pollinators which makes them a great addition to your landscape.

So, there you have it; this year’s class of Oklahoma Proven Plants from Oklahoma State University. To learn more about Oklahoma Proven Plants from previous years, go to our website, click on Lawn and Garden Help, then Flowers. See you in the garden!

You can get answers to all your gardening questions by calling the Tulsa Master Gardeners Help Line at 918-746-3701, dropping by our Diagnostic Center at 4116 E. 15th Street, or by emailing us at mg@tulsamastergardeners.org. Photo: OSU Ag. Comm.