I'm still wondering why go to all that fuss and take the risk when you can keep it in a pot, cut it back and bring it in the house for the winter? If you only have one or two they won't make a jungle out of the house as long as you cut them back enough. The two huge ones on my patio - see pic - were cut back by about half in late September. They love it. Both have buds coming along, although we are getting a cool night or two coming up, so we'll see. I'm going to prune them again after these blooms finish, to let more sunlight onto the orchids.
If you can get yours blooming a month earlier next summer because they didn't go dormant, you will be rewarded with at least one, maybe two more bloom cycles before fall temperatures hit again.
IF you do leave it outside, wrapping the stems won't help. They will just die back/rot faster because the wrap will keep them damp. The plant will die back right to the ground anyway. Only the parts that don't freeze will survive, so it really just depends how cold it gets and for how long. Good luck, whichever way you go.
