My trumpet vine is growing vigorously, but isn't blooming. Why?

FAQ
Question: 

My trumpet vine is growing vigorously, but isn't blooming. Why?

Answer: 

The trumpet vine (Campsis radicans) is a woody vine that produces orange to reddish, trumpet-shaped flowers.  After planting, trumpet vines often don’t bloom for 3 to 5 years.  The trumpet vine has to grow and mature before it is capable of flowering.  There is nothing that can be done to force the vine to flower.  Eventually, the trumpet vine will bloom.