Answer: Trumpet vine, Campsis radicans, is normally a very fast and rampant grower with few problems. It blooms on new growth of the season and can sometimes be encouraged to bloom by cutting it back hard in early spring. (Do not prune it after that because you will cut off the new growth where flower buds will form.)
These plants prefer a sunnier spot than yours seems to have and this may be the root of the problem but I suspect your plant may be suffering from a possible number of problems.
You might check carefully for aphids. (Aphids are most attracted to overly tender, succulent growth such as that caused by an oversupply of nitrogen especially if combined with lower light levels.) Aphids may be feeding on the growth tips causing distortion, with a black fungus then taking advantage of the aphid damage. The fungus will grow best in a shady area especially combined with poor air circulation. If there are no aphids, there may be a blight or leaf spot problem. Your County Extension (461-1000) should be able to help you identify that and make control suggestions.
If none of the above seem to be the case, I would suggest moving the vine to a sunnier spot (sun all day or at least all afternoon) in early spring, cutting it back hard when you move it to compensate for root loss and to stimulate new growth, and fertilizing it very little if at all. Water it until it is re-established and then look for blooms.
Good luck with your vine!
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