Dendrobium gratiosissimum?
 

I'm thinking of getting one of these, it's beautiful.
Tried to find some info on the culture of this species but it's very difficult to find and I'm asking you for tips. I've understood that it needs a long dry period with low temperatures.
The thing is that I got this perfect cold plant room that stays about 45-50F during the winter and a green house during the summer. With some humidifying does this sound like a good resting place for a gratiosissimum during the winter? I'm also thinking about keeping different Cymbidiums and Coelogynes there.

Dendrobium gratiosissimum is a nobile-like dendrobium. It means that a dry winter is needed for the species. Generally, while they stop growing in late autumn, you should decrease the water gradually. In winter, the medium should keep dry as possible.
Besides, summer care should emphasize on lowering night temperature since it is an inland or highland species. The light level for them is as that for most large-flower cymbidiums, especially during winter rest.