It is a very difficult thing to do but you must. Trim your lanky sprawling perennials back now. These three blooms will be lost but you will create a bushy plant with loads more blooms.
Trim all your heat loving perennials now so you will have a spectacular show at the beginning of this fall.
These photos were taken at the end of May. Stay tuned, I will get a photo of the plants now as well as other plants and their transition after pruning.