How deep did you plant it? If the crown is more than 6 inches deep, that could be a problem.
Like Liz said, if water pooled on it, that could cause root rot.
I had 4 Bartzellas that I got from Lowes in 2012 just bloom for the first time this year, and believe me, I have been babying the heck out of them! So it may not be anything you have done wrong.
They are so worth the effort though.