The problem with the misidentifications is that many Alpinia and related genera have spp with fragrant leaves. It isn't a means of identifying any particular species. There are different commercial varieties but the ones I've seen in private collections usually top out at 3-4 ft. The inflorescences do appear on basal shoots similar to most Zingiber spp as was mentioned (though some Zingiber bloom terminally and a few basally and terminally). To non collectors the species do seem similar so the confusion is understandable, but worsened by sellers knowingly selling mislabeled plants to those in search of the spice plant. Tim Chapman