Gardening and Horticulture - ornamental grasses

when is the best time to trim these grasses back ,or should you not at all?

You should cut them back when they are dead and dry. However, I would leave them on until the new growth is just starting to appear in the spring, because the brown stalks and dry flower heads add a lot to the winter landscape.

LEU----does that go for lirirope too?

I've heared that it does, and that's what they do here at the University of Georgia. I think they go over the vast areas of it with a mower. I'm not sure about the reasoning, as I don't deal much with Liriope - I really don't like it, find it very dull.

i'm not very impressed with lirirope either- but my new house has many plants, shrubs, and trees already established. i hesitate to cut any of them down untill i know what i'm dealing with. since they are established- they must be doing well in my yard, and who does'nt want a low -maintenence, functional plant? the main reason i want to keep them , is to use as a low maintenence plant to underplant new azaleas with. but i appeciate your response and look forward to hearing from you in the future.thanks.