Is it a Campsis radicans, the common orange variety? If so they can take a few years to reach blooming size. They do well in poor soil. I only watered mine in the beginning to get it established and I've never fed it. I didn't know how invasive this was when I planted it and finally stopped trying to kill it when I realized it was futile and it was indestructible. lol
Karyn

I have had mine going on four years now. I planted two trumpet vines on each trellis ( I have two ) and only this year did I finally get two sets of flowers on one of the trellis's. I hope mine bloom on both trellis's next year. Keep the faith, it WILL bloom :)