Think of the conditions in the FL, Everglades and that's how a ghost orchid should grow best, would that be "sub tropical"? From sping until fall I'll be growing mine in the hot Lowland terrarium and then put in the cool highland chamber until spring to give it that temp variation. Indeed Polyrhizza is not a petty plant but I like interesting plants more than pretty. A snarl of slivery green roots that blooms a big white flower is interesting! My pals orchid shop has several rarer ghost orchid species than the US one from the Adaption movie but I've yet to see any of them flower to see how they differ.