No, not yet! Just clean them up. Clear away all the brown & dried up bits. That will improve the appearance 10 fold. The plant needs to store up energy for the winter & next spring's blooms through photosynthesis. It may yet sprout a few more flowers like mine has.

Thank you Bathgate, that was a speedy reply.
I will take your advice and leave them alone 👍

I've cut mine back lol Maybe I should have waited.

If you want to divide them in the fall, they need about 6 weeks before the first frost in your area to develop new roots. There are a lot of how to videos on You Tube. At that time, you can cut back the green foliage. I prefer fall dividing because the plant has time to recover and will usually flower the next year. Also, it will survive dry summers better. The fat roots are where the plant stores water to get it though lean times. You can also thin out the root system a bit of all the old, skinny ones. Just remember the crown goes at the soil surface so rot doesn't set in.
A lot people will do it in the spring, when the ground thaws and before growth starts.

Thank you Wylie for your very useful tips. I think I will try them because I would like to split the plants as they have grown to big where they are.