Here is a photo of Hoya megalaster showing its buds.  It is living in very tight quarters crammed into a grow tent with H. elliptica, which you can see in the foreground.  It is way too hot in my grow room and these plants seldom ever see temperatures that drop below 80°F (27°C) night or day.  It is not ideal, but because of the heat generated from the lights there is little that I can do about it.  These warm growers don’t seem to mind too much.