Desert willow is a drought tolerant Texas native from parts west and South and way into Mexico. It can often be found on the edges of arroyos and stream flats that emerge from the dry hills and mountains. Once established in our region, it will never need watering. After a few years in the landscape, this tree is quite comfortable in a full sun very well-drained spot in East Texas.
The desert willow is a member of the Bignoniaceae and native to the dry climes of Texas and Mexico. Closely related to catalpa, flowers are in racemes and now come in a variety of colors from lavenders with dark splotches on the throat to the pure whites. A small tree to a little over twenty feet, the species has fine-textured leaves and the habit of a big flower show in late spring and early summer with waves of bloom throughout the remainder of the year.
The species is easy to root and fast – rooted cuttings should be removed from the mist bed as quickly as roots are noticed.
While common in western parts of this state, the desert willow is rarely seen in the pineywoods and points east. The key lies in situating the plant in a full-sun dry location and providing good soil drainage. Raised sandy berms are ideal. In Mexico, the plant is common in hot, dry washes and arroyos and along the sides of streams and creeks. Cold hardiness suggests the plant be used in zones 8 and 9. While our plants easily survived the 1989 zero degree event, there was some twig dieback at the tips and in the interior of the plant; in fact, the species is a bit prone to retaining numerous dead twigs – an occasional twiggy growth pruning is all that is needed to spruce up the tree.
We have two cultivars and one seedling in the garden. ‘Bubba’ is the showboat and the SFA Arboretum is home to the world’s tallest ‘Bubba’ (according to Paul Cox of the San Antonio Botanical Garden and the originator of the variety), a twenty year old, 40-foot specimen parked on the hot western face of the Art building. The variety never fails to elicit praise. Before the variety went commercial, Paul insisted that the name be kept as ‘Bubba’ if it were to be sold in commerce. Smart move. ‘Bubba’ is very floriferous with good show throughout the summer and fall. ‘White Storm’ sports white flowers on a beautiful small tree. Once well-established the tree deals with drought in East Texas beautifully.
As for other varieties, there was a time when I cared more. I sought out varieties from far and wide and put together a collection for the Chilopsisfiles. Unfortunately, in my region I was pretty much the only member of the fan club. George Hull, then at Mountain States helped a lot with several varieties. A number of western nurseries sent me some wood. At one time, Dr. Jimmy Tipton in west Texas had a number of selection that looked good. ‘Marfa Lace’ seems to be one that stuck in the trade. Some of these still exist at SFA Gardens. Some do not. We have a good white we’ve enjoyed for years and a couple of others via JBerry Nursery that look good, but, to be truthful, you’d have to go far to find a better variety than ‘Bubba’, a Paul Cox find that has performed beautifully in the wetter and more humid region of Texas. It’s a sad name and one that I thought would put it in the to-be-avoided category, but I think it’s helped sell the darn thing. It’s certainly the number one variety in Texas. At our plantsale, we often sell seedlings of ‘Bubba’ and we call them the SFA Gardens ‘Sons of Bubba’ series . . . abbreviated, of course, to the SOB series . . . but I learned that’s a bit too edgy for the mass market and, I guess, it’s way over the line for this University’s administration.