Question
I purchased 2 flats of dahlias and after four weeks there is only one with a bloom.  Am I doing something wrong or is there a possibility that some just don't bloom and why would it be all of them?  I have fertilized them, watered them, and followed all the things I do every year and to no avail.  My dahlia bed is usually gorgeous.
What can you suggest?

Answer
If you have grown them before then I persume they get enough sun. It could be that they were deadheaded before shipping and just need some time.

The best advice I can give is to wait, and then stop being so good to them. Sometimes they need a bit of stress (a bit, not a lot) to flower (flowering is induced as "panic" action by plant because all of a sudden reproduction is top priorty). Try to hold water a few days longer than normal.

Also, do not add more nitrogen fertilizer. use 0-10-10 if needed to fertilize again.