Jelinda: Very healthy looking Hoya's you have there ... great growing! The one in your first photo (Hoya carnosa 'Chelsea'):
Wax Plant (Hoya carnosa 'Chelsea') is one I've had for a few years and it's never bloomed. I actually have two of them, one is a small plant from a cutting that I received in trade four years ago and the other is an Exotic Angel plant that I purchased at Home Depot a couple of years ago. I think I noticed a peduncle on the small plant but it's hanging out in a tree off the back deck and I need to check it more closely to see if what I'm seeing is actually a peduncle. Although I know the flower is pretty much like other carnosa's, I would love to see a Chelsea bloom! The Hoya curtisii (in your last photo) is one that I've never had any luck with but I read that it requires cooler conditions so I know the heat and humidity is what killed them here. If I ever try Hoya curtisii again, it will stay indoors year round in the air conditioning!