Undeterred, I asked one of the staff at a local nursery if he knew why my trumpet vine wouldn't bloom. He asked me if I fertilized it and I nodded yes.
I was about to give up and dig it up, but decided to put up some lattice for it to climb up. My friend Bev came over and gave me a lesson in using a circular saw and suggested using deck screws that wouldn't rust. I'm not mechanically inclined, but if you show me how to do something I can manage. Up went the lattice and the next year I got flowers for the first time. The trumpet vine didn't bloom as a direct result of putting up the lattice, but I now know how to use a circular saw.
Fortunately, the Bridges penstemon are not so complicated.