Trumpet vine has never bloomed
Trumpet vine (Campsis radicans atropurpurea) was planted last year but has never bloomed and this is the 2nd year in the pot.
I would guess that the nitrogen to phosphorus ratio is off. The soil may have an abundance of nitrogen, which would result in nice, healthy green growth but little to no blooms. Without the right amount of phosphorus, it will not bloom well. Bone meal is a great way to add phosphorus.