Cautleya died here (Knoxville, TN) in my Z 7 the first winter. Several Roscoea are doing well, but they must want richer and moister soil. Hedychium Dr. Moy, greenei, spicatum, coronarium, and another hybrid have done well here and multiplied. H. gardnerianum is hardy, but not worth growing here.
Zingiber mioga (the same clone JW has) liked Kansas far better than here. My patch in Kansas has been there for ten years and is a meter or two wide by a meter. This clone is ex DJHC from Japan.
Strangely enough, Alpinia zerumbet has wintered for two years as a deciduous plant, thus making it not worth growing.
Aaron
--- On Thu, 7/1/10, James Waddick <jwaddick@kc.rr.com> wrote:
Never tried Cautleya, but would appreciate experience from other growers. Googling suggests Zone 7 and warmer.