Iris stem splitting just below bloom

Question

Had these iris for years. Have never seen anything like if. Recently transplanted from another location and we’ve had a lot of rain although my other varieties aren’t doing this.

Answer 1

The weakened flower stems could be due to the transplant.
It can be sign of the plants needing to be divided though my research shows many gardeners list heavy rain and wet soil as conditions that also can cause this issue.