I have searched a bit on this subject and have not found an answer. I have a large planting of Carex Comans 'Frosty Curls' that have looked amazing for several years. This summer however the clumps have lost much of their blue/ green hue and are brownish yellow. I have combed through the clumps multiple times pulling out the dead and old but still there has not been very much rejuvenation.

They are sited in mostly full sun (although its seasonal in Seattle ; ) I have also upped the watering thinking this may help but they still look like brown mops. I recently tried to experiment cutting back several of the clumps to the ground but so far there has been no new growth.

So my question is can i rejuvenate these plants? I really love them in their prime but they are a mess now. Can i cut them back and when? How far should I cut back?

I have gotten a ton of baby plants from seeds and have planted them elswhere in my yard and so far these are doing well. But, this would be my last resort for rejuvenation since I will have to look at a desolate front yard all winter!