This is not a commonly grown species and I am not sure if any forum members grow this one but I don't.
According to the Hoyor.net site this species does not like direct sun so it is good that you have a curtain on the window. As for water it is recommended that you not let this plant dry out.
Good luck with this one it's a beautiful plant.

Mike

Here is a link that might be useful: Hoya inflata on Hoyor.net

Lalla....I grow my H. inflata in artificial bright light...and never let it dry out. It's potted in a "fast draining" soil mix...and in my experience, it's a very slow grower...sends out long vines, rarely with leaves, and the vines usually die back. A beautiful hoya. I may try adding lime to the soil to see if it promotes more growth. Best wishes, Patrick

i thank you very mutch !!!!!!

patrick,i will follow your instructions!!!!

I was having the same issue of long leafless vines and losing the leaves that it had (down to two leaves). Then I put mine outside under a garden umbrella for the summer and still no blooms but at least there are some new leaves. I have the plant growing in a clear plastic storage box that gives it good humidity and (I think) helped to slow the loss of leaves before I put the plant outside. The water that I give the plant has low TDS and the plant is growing in hydroton, so I believe it is fairly neutral PH. Would love to know if others are growing at a different PH level with better results.

Thanks Denise, I might try putting mine in a tree next year.