Question
this year my plants got about six foot tall but four of them had no flowers and one had just four flowers.what happened?

Answer
Hi Rich

Did you cut them back hard last fall?  That's the usual reason why these problem-free plants don't flower.

If you have to cut them back, or down, always cut to just above a pair of good, healthy buds.

So - don't worry - things should be back to normal next year!