kimberely,
I have both.
Don't cut either one down at all.
They need a great deal of water, if you have sandy soil, i am not sure what your soil is like.
You might want to put down a drip hose to make sure they
get enough water.
My blue fescue really never did very well.
It is still alive, it is a cool season grass, which means it loves the cooler weather in the winter.
I personally wouldn't plant it in the front of my house, but see if it turns blue this winter and if you like the look of it.
I wasn't impressed with the pink muhly grass, but that is just my opinion.
I planted red head grass, it is awesome.
I also planted silver Miscanthus grass, also awesome, and I water the silver grass constantly in the heat.
I also planted Mondo grass, which was a dud. i think a small little bit is still alive, but don't buy it. I gave it 4 years, and it is almost gone.
I love grasses, but some grasses really need alot of water, and some are quite drought resistant.
Hit or miss.

I cut my Blue Fescue at least twice a year; once in mid-summer and once in early spring.I cut it down to 1/2 or 1/3 of its original height. As a cool season grass, it goes dormant in summer, and tends to look ratty. After cutting it, it will send up a nice flush of new foliage. The summer cutting takes place after it blooms, but before the flower stalks turn tan in color. It self-sows here, quite actively, so I cut it before the seeds ripen.

Pink Muhly is due to bloom now; September to November. It's a warm season grass, and should be cut to the ground in late winter. I stopped growing it because it only looks good when it's in bloom.

Once established, both grasses prefer dry to medium dry soil. All newly planted grasses should be watered regularly until they get established, which takes at least 1-2 growing seasons.

Thanks butterfly and donn for your responses.
donn since I missed cutting back the blue fescue in the summer I guess I should just leave it as is..is this correct? As far as the grass looking ratty, I'd say some of it looks dead. I'm so disappointed. I take responsibility in not doing my homework concerning this grass. I explained to the landscaper as far as how much sun the front of the house gets, etc. and he picked the plants. If I don't see any improvement when the cool weather sets in I will call the landscaper and see about making a change. We spent too much money to have dead plants.

Kimberly, I would cut the Fescue back now. Just trim it back by half, into little round hedgehog-looking balls. It shouldn't make any difference to the landscaper as far as making good on the plants he sold you.

Donn,
Please keep an eye out for the post tomorrow. Tomorrow we are suppose to have a nice sunny day and I will take a few pictures. Hopefully you will be able to tell me if some of the grass is dead or if there is hope. Stay tuned.

Donn- the situation with the blue fescue has been solved. I sent pictures to the landscaper, majority of the grass is dead and they are going to replace it. The reason I chose the blue fescue is because I wanted something different and not the standard liriope that so many have. What does he want to replace the blue fescue with? You guessed it, liriope. Can you think of any other border grass that does well in upstate South Carolina and that loves lots of heat? The house sits on the west side and gets very hot afternoon sun. Thanks

Check these:

Dwarf Pennisetums (Pennisetum alopecuroides) 'Little Bunny,' 'Little Honey' and 'Piglet.'

Many Carex varieties are low growing and can take full sun.
Carex aurea
Carex davalliana
Carex dipsacea
Carex flacca
Carex muskingumensis 'Little Midge'
Carex pensylvanica

(Note, full sun Carex require irrigation, but they're worth it.)

Imperata cylindrica 'Rubra'

I have two different cultivars of blue fescue right by my front door and love it. It always looks good here. I never trim it down like I do my warm season grasses. I wish it seeded but it doesn't.
My climate is much different than yours though.

Thank you all for your responses. I have a dilemma, finally after speaking with the landscaper we decided on replanting the blue fescue. The landscaper had shared that he had some great looking plants of the fescue. He was indeed right. There was no comparison on the quality of the plants from what was planted this past spring and what they put in last week. The problem is we were short on 6 of the plants. They have informed me that they are not going to replace the 6 left. We got what they had available and that was it. Personally I think they should have followed through and finished the job. Any ideas of where to purchase more plants in the upstate?