By Bill Ward
Published in The Boerne Star in July 2005
Clematis and passionflower are two of the most popular vines cultivated in home gardens. The horticulture trade has produced hundreds of cultivars of these plants so that many colors of large-flowered clematis and passionflower are available at nurseries.
The Texas Hill Country has its own versions of clematis and passionflower. They are fairly common around Boerne.
The native clematis that provokes the most oo’s and ah’s is the scarlet leatherflower or Texas clematis (Clematis texensis). During the spring and summer it produces inch-long blooms composed of four leathery red sepals, which are spread apart only at the tips of the flowers. A good place to see this low-climbing vine in bloom is along the downstream part of the Creek Trail at the Cibolo Nature Center. Usually the best time at that locality is late spring and early summer.
I suspect the scarlet leatherflower is not widely available for purchase in nurseries. However, Chuck Janzow usually has a few for sale at Cibolo Nature Center’s Mostly Native Plant Sale in April. These are slow-growing vines that take up little room in the garden. They grow and bloom in both shady and sunny spots.
The scarlet leatherflower is endemic to the southern and eastern Edwards Plateau and a few counties of North-Central Texas. The purple version of the leatherflower (C. pitcheri) is widespread across much of Texas.
Another clematis native to much of Texas is old man’s beard (C. drummondii). This vine climbs over shrubs and fence lines and becomes particularly conspicuous in the late summer when it produces clusters of one-seeded fruit with tails of long silky hairs. These “beards” linger on into the winter.
Seven species of passionflower are native to Texas, and three of these occur in the Hill Country. In East Texas, the large maypop vine (Passiflora incarnata) with its eye-catching lavender blooms is easy to recognize as a species of passionflower. In the Hill Country, by contrast, the little passionflower vines go largely unnoticed or they are weeded out as one of those little nuisance vines that come up in the yard.
Our Hill Country passionflowers seem miniaturized. The vines do not grow more than three or four feet long, leaves are small, and the light-yellow-green flowers are an inch or less wide.
The bracted passionflower (Passiflora affinis) is only found across the southern part of the Edwards Plateau and into northern Mexico. It has three-lobed leaves and is similar to the yellow passionflower (P. lutea), which also grows in the Hill Country and much of eastern North America. The other Hill Country species is the birdwing passionflower (P. tenuiloba). In this species leaf shape varies from two to multiple slender lobes. It ranges from Central and South Texas into New Mexico and northern Mexico.
At least two of the Hill Country passionflowers come up naturally in our backyard. They seem to thrive in the dry soil under the liveoaks. It helps to use a magnifying glass to enjoy their blooms.
Other interesting vines in the Hill Country are the milkweed vines. Our area has two similar species, the pearl milkweed vine (Matelea reticulata) and the uncommon plateau milkvine (M. edwardsensis). Both of these vines twine over fences, brush, and small trees, climbing several feet high in some places. Both have heart-shaped leaves and small star-shaped green flowers less than an inch in diameter. The pearl milkweed vine is distinguished by the tiny pearl-like silver ball at the top of the stamen column in the center of each flower.
Three years ago, I transplanted one of the pearl milkweeds to a spot under one of our backyard oaks. It has come up and flowered every year since.
Perhaps my favorite vine that happened to come up in our backyard is Lindheimer’s morning glory (Ipomoea lindheimeri). This vine produces large lavender-blue flowers from spring to fall. Unlike the smaller-flowered purple bindweed (I. trichocarpa), Lindheimer’s morning glory is not invasive and can be easily contained in one spot. If all goes well with propagating my seed, there will be some Lindheimer’s morning glories for sale at next spring’s Mostly Native Plant Sale.
