Non-flowering fuchsia

I have two fuchsias in big containers. They got blasted in the freeze but did survive and I have nurtured them as much as poss, but even tho' they've come back to about 18"x18" from ground zero they have yet to produce any buds. Has anyone else had this problem?

Thanks MoS, I have been feeding with Phosphorgen(wrong spelling I think, but U get the drift) but will try tomato feed instead. Its getting so late in the season now, but at least I didn't lose them