what type of gingers? I'd wait until they go dormant. (if that's the type of ginger that will). Any leaves or chlorophyll on it will help it to recover. Once new leaves come out, go ahead and trim the old ones.
kevin

Shredded my hedychiums. I cut them all back to the ground. The shell ginger only blooms on old growth so if you cut it back you won't get blooms next year. Tally HO!