The verdict is in. Thunbergia battiscombei, also known as Blue Boy, Blue Glory, Clock Vine is a winner in my garden. It has survived the past two winters and has come back into bloom this spring. I don’t remember where I bought this plant/vine but I know I’ve had it for about 10 years. It is a vine, but tends to grow more like a shrub, with many stems emerging from the base. I keep it contained in this trellis as it tends to flop over easily. It’s bushy and grows about 5-6 feet tall where I have it planted (sun/part shade).
The leaves and stems are rather large (hence it’s tendency to flop over) given the size of the flower (petunia sized). The color of the blooms is a deep, rich blue-purple with a golden yellow center. The shape of the flower is trumpet like and has an interesting view from the side. Notice the curves. The buds are hairy and have a unique vascular pattern that is quite beautiful all by itself. The bloom extends downward from bud and curves back upward.
A reliable bloomer from late spring to early winter in Zone 9, however at the first frost, the stems gets mushy and this vine dies back quickly to the ground for the winter.
I haven’t paid enough attention to this plant to see if I could propagate it easily. It does not appear to seed itself easily as it has been in the same place for 10 years, and I have yet to see it pop up anywhere else in my garden (that could be a good thing). This year, I am going to try softwood cuttings or layering. On Dave’s Garden, it does mention that you can collect the seeds of the dried heads. Floridata.com also has some very good information on Thunbergia battiscombei. If you have not visited Floridata.com yet, have a look. I find it a very helpful reference guide.