I think you should not strip them bare before frost. A few leaves act as insulation for the crown and stems, and the plant can photosynthesize on mild winter days. Pile 4–6" of straw, shredded leaves, or compost around the root zone to buffer soil temperature and protect the crown. In colder zones, wrapping the main stem loosely with burlap, frost cloth, or even piling up extra mulch around the lower half of the plant can help prevent winter kill.
