It could be related to dehydration or the type of cutting tool used (bypass shears, etc.) pinching the soft interior but just based on this picture I am not sure you will still be able to root it.

I guess it could be dehydration. I doubt it is my pruners because I have never seen this before and have rooted dozens of cuttings, all cut with the same pruners. I even initially cut this one with the same pruners and did not see this hollowness.

I don't know if it will root either.

Odyssey,

You have nothing to lose and a plumeria to gain by trying.

That black area is rot ... remove it. You should see all clean white. Dip in rooting hormone, pot up (cut clear plastic bottle with lots of holes on the bottom) in relatively dry soil, mist soil & cutting), place the entire pot & cutting in a plastic bag (to increase humidity) with just a bit of an opening at the top to let in air.

Mist weekly. When you begin to see new growth, bottom water by allowing pot to sit in a dish of water 10 minutes once a week. When you see roots, water normally.

After a month, repot, water & fertilize after a week. Sending good vibes your way for good rooting!

Maria Elena

Thanks Maria Elena. There was no black area on the bottom of this cutting--the area that is darker is a hole. The middle of the cutting had pulled away from the side.

I decided I did not like how it was looking and cut quite a bit because it was hollow for a long ways. What was originally a nice 3 branch cutting is now 3 separate probably too short cuttings. We'll see what happens. I have rooted lots of cuttings and never seen anything like this!

Ahhh ... Got it. Plants do what they will, right. Hope they root for you.