Kenni Judd wrote:
Sarah: If the leaves are wide and thick, and esp. if the plant is spiking
or flowering now, it's probably gigantea. Rhy. coelestis is a
summer-bloomer and looks more like a "typical" vanda; retusa is far less
common. I suspect you can find pics of all 3 on Jay Pfahl's Orchid
Encyclopedia site and ID it, even if it's not in bloom.

Rhy. retusa looks, plant-wise, somewhat intermediate between gigantea
and coelestis. The leaves are wider than coelestis and longer (but
shorter than those of a large-sized gigantea), and have some subtle
lighter veining like gigantea (and unlike coelestis). Retusa blooms
in spring/summer, as does coelestis, while gigantea blooms in the
winter.

---Prem