Sorry old thread, I know.

Lydia, leafless cuttings (rooted or not) of plumeria are usually sold in colder months when they go dormant (forced dormancy in some locations) and lose their leaves.

Growers will often also make cuttings and remove the leaves so they don't spread any mold or bacteria due to decomposition during the curing process before shipping or rooting.

When you take a plumeria cutting, an abundance of latex sap comes out. The cure process is to allow the stump to callous over so rot does not set in. When I make cuttings, I quickly sweep my blowtorch over the bottom to "cauterize" the wound. Then, I place the cutting in a cool, dry location to cure for a few weeks. Once the stump has calloused over completely, it can be rooted or shipped.

The reason sellers send leafless plumeria cuttings is in part due to the cure process, but also, in my experience, because until the leaves mature, they are quite prone to falling off with the slightest touch, which is obviously bad if you are going to ship them.

That being said, you can ship rooted plumeria tips with mature leaves just fine.

RE: hoyas, you can absolutely root leafless nodes, although it is not simple to do so.

I have rooted one node cuttings with one leaf just fine, and have also rooted cuttings that were 2+ feet long. The only difference I have noticed regarding the size of the cutting is the regrowth rate.

If my cutting had one leaf but new growth starting, it grew quickly after rooting was established. If it had no growth starting, new growth would take awhile after rooting was established.

This, in general, did not hold true to my cuttings with more leaves/material to work with. Unless they were slow growers to start with, all of my larger ones seemed to restart growth quickly after rooting was established.