If it's really Elephant Grass, it isn't hardy in your zone. It doesn't tolerate frost, at all.

Thanks Donn
I didn't think Pennisetum purpureum was hardy in z5. Is there another grass that might have a common name of Elephant Grass or a grass that people call elephant grass because of the look?

Grasses2..I don't know of another Elephant Grass, but there's another grass called Pennisetum setaceum 'Purpureum' which is also not hardy in your zone.