Phlox problem

I was wandering around my garden today as for once it WASN'T raining and noticed a clump of Phlox was keeling over. On closer inspection many of the stems of the Phlox had split open and gone "woodie". Would I be right in thinking that this has been caused by irregular water supply? We had a very dry and warm March followed by a deluge in April. I have had this clump for quite a few years and not had a problem with it before. If I cut all the affected stem off they are about 7 ins tall atm, will I get flowers this season or not? Hope someone has the answer,thank you.