Strawman, your plant certainly looks healthy to me, and I can't see anything that you're doing that would keep it from growing... has your weather been unusually hot? If so, that could certainly be causing them to not flower temporarily. Better Bush are supposed to be "compact plants," but not quite THAT compact -- I wonder if the plants you bought could possibly have been mis-labeled and are actually a different variety (like 'Patio" or something).
Maybe
@NewYorkRita has some insight to offer!
