That's happened to me before as well. That's why I'm asking for help or suggestions on my Globulosa. Actually, when all else fails I just stick them in a vase of water. They usually all root (although I know there's a big difference between water and soil roots) and stand a much bigger chance of survival once potted up.

Some of my Hoyas have done so well (growing like weeds) in water that I'm afraid to pot them up because I'm sure I will eventually over or under water them and kill them. So for now I'm leaving them alone.

Sorry, I don't think I answered your question or gave much help - lol. I'm sure the experts will comment with great advice.

If they are going to rot wouldn't sticking them in water make them rot faster?

Do you have a light and hood over your aquarium? The heat from the light (even though I use a florescent) keeps the space warm enough. Since it's winter there, you may lose 50% of your cuttings - I don't have as much success in winter either. But I'd suggest you root them in perlite - chunky perlite if you can find it. I keep just a bit of water in the cache tray under the pot which the perlite wicks up. It seems to give them the perfect moisture to air ratio for good strong roots. The only way to save those that are rotting at the stem is to cut above the rot and try to root what's left of the stem. Good luck!

Denise in Omaha

Rooting in winter definitely works against you. Too much heat and humidity, especially indoors may rot the cuttings. It could be too hot in the room from the heater or the bottom heat is cooking them. What Denise suggested sounds perfect to me. I've rooted my Hoyas on a desk in my office with no bottom heat or supplemental humidity or light. Just indirect light from a window and I gently misted them if they looked too dry. I've rooted pusilla, calycina, lacunosa, and compacta this way. Good luck and even if half make it I guess that's not so bad!