Carol: I'm so glad you saw this thread! I've learned so much from you about Hoya's the past few years but unfortunately I seem to get brain freeze sometimes and should not have made that statement about curtisii preferring cooler temp's. Geesh, I really don't like perpetrating the spread of incorrect information and that's exactly what I did ... I am so glad you saw this and posted!
Hmm ... Now I'm wondering which Hoya I lost from the heat and humidity. I haven't grown that many Hoya's but for the life of me I can't remember which one I had that I was told it probably succumbed because it was from a cooler region. I used to have a list of information on the my Hoya's but lost it when my computer crashed a few years ago. I'm still bad about remembering to do backups!
Jelinda: Please listen to Carol, she has grown Hoyas for a long time and is extremely knowledgeable and helpful when it comes to these plants! I don't have a greenhouse but I find that my hoya's do much better outside hanging in the trees or sitting on the deck than when they are inside the house. I totally agree that good air circulation is critical, not just for Hoya's ... but for all plants.