Hi and Welcome jm19, I ususally don't, I've heard that they use the energy from the leaves. But then some of my friends always do. Last year we had a really cold winer here, and the rabbits ate them down. Many of those didn't bloom for me. Although they ate them clear down to the rhizome. I think it's more important to pull off the dead leaves in the fall and again in the spring. Some people burn them off in the spring if they are where they can be burned.
