Hmm, I don't think it's generally recommended to cut back Festuca. In the past, when I've tried it, they've died. I just "comb" out the dead stuff.

what about forgetting about the tops... and just giving them a beetles hair cut around the sides??? .. and if it dies.. it dies.. i dont like it anymore ...

on the other hand .... i can see in this natural state.. its kinda two tone cool... left to nature ... very sand dune-ish ... i could easily convince myself.. that life is to short trying to give a grass a 'do' ...

ive spent a lot of hours in a lawn chair convincing myself that things look better in their natural state... lol ...

ken

That looks a lot like my Festuca glauca 'Elijah Blue'. When grown right it is very attractive, but too often this is what I see. It’s a frustrating plant.

If you can get all of that dead stuff out, you’ll probably end up with something that looks like this:

Mine had almost as much dead stuff as yours before I combed it. Now, I can see about eight plants, and I can move some, or just pull some and toss, or ignore for another year. You can comb from the base (hard) with a garden claw or a hair brush or whatever works. New growth will come out along with the dead stuff, but the plant(s) will recover.

Though it is frequently employed in ground-cover masses and can be quite stunning in this manner, its short-lived nature guarantees that a fair amount of maintenance is necessary to keep plantings looking neat and uniform. Individual plants tend to die out in the center after two to four years, especially if stressed by summer heat or water-logged soils in winter. In any case, annual shearing in late winter often contributes to longer life and neater appearance

-- Dick Darke, The Timber Press Pocket Guide to Ornamental Grasses (2004, Timber Press, Portland/Cambridge)