You can root the cutting while it is still attached to the plant by pinning it with a bobby pin down into some dirt in another pot that you sit right next to the one the mother plant is growing in. However if that broken piece is not connected enough to be getting any sap from the mother plant anyway, you might as well just cut it off at the break and root it like a regular cutting. There are many ways of doing that. Some people just stick it into a container of water like a bottle of some sort. They say if it is colored like amber or blue it does better. One could use a beer bottle for instance. This looks like a type of hoya that would root in water OK.
Other people use pure perlite in little clear plastic cups that have holes burned in the bottom for drainage. Most people either cover these with a large clear plastic bag for humidity or place into a clear container like a pitcher or aquarium. However you do it, you must set it in a well lit location like a windowsill, but it doesn't need full sun on it. You don't really have to have bottom heat, but it helps speed it along. You should keep the plant in a warm place if possible. It is true that it is a bit harder to root plants in the fall & winter, but it is not impossible. Just give it what it requires and it will root. There is lots of info in these forums about rooting cuttings. Good luck.

Thanks, Mairzy. I would like to keep it attached, it is getting enough energy from the mother plant to keep it healthy so far. Would you pin it so that the first leaves are in contact with the soil, or the whole vine?
I am not sure yet exactly what I will do but I appreciate your help!
Tami

I don't know of folks air layering Hoyas, not sure that's the way to go. Most folks would try it water rooted or into mix itself. Suppose it may work, I guess you'll find out.

yes, the first leaves plus as much of the vine as will lay down on the surface of the dirt. You can even break off a leaf & put the node down on the dirt & pin it down. The roots will come from the nodes where the leaves are/were. It will grow roots from the vine laying on the dirt also, but the main big roots will come from the nodes. You can cover the vine up a bit with some loose soil too. Some use rocks to hold the vine down.

I accidentally ground layered my H. macgillivrayi this summer. One of the stems had fallen onto a nearby pot and rooted. I didn't pin the stem but it was pressed well into the soil. Maybe from being rained on??? I discovered it when I went to move it into the greenhouse a few weeks ago. I have absolutely no idea how long it took for the stem to root.

Somebody here does propagate their Hoyas exclusively through air layering, and I think most of us have done it at some time or another. Sue describes using the classic sphagnum moss method in this thread, too.

Carnosa is too tough for you to worry about it being the wrong time of year. It might take a little longer, but your likelihood of success is very high!

I planned to try to root it while still attached as Mairzy suggested but the leaves on the segment felt a little soft to me. I ended up cutting it from the mother plant, soaked it in water for a couple hours, dipped it in rooting hormone, and placing it in soil with a bag over it last week.

I found a plant heating mat yesterday so am going to put the pot on it. Hopefully it will root, if not I will have at least tried. I have a couple vines from my lipstick plant that I did the same thing with.
Thanks for all the help. Tami

I checked the cutting yesterday and I HAVE ROOTS! I am very excited, I was pretty sure that it wouldn't root at this time of year. The lipstick plant cuttings seem to have roots but the leaves are quite droopy, still green though.
Thank you all for your help.
Tami

Tami,

What do you mean you checked the cutting & you have roots? Did you lift it out to do this, or did you tug on the cutting? If so, I'd suggest pls. don't do that as it breaks the very roots we're trying to encourage the plant to form.

When you see new growth, any new growth at all, then you can be sure it's rooted.

Cuttings can root at this time of year, sometimes it's just more slowly.

Hi PG, I placed the cutting in a small clear plastic solo cup to root. I looked around the outside of the cup and saw a couple fat white roots. No tugging or pulling required. No new growth yet but the leaves remain plump and firm to touch. So far so good!
Tami

WHEW! You had us worried that you dug it up. LOL