Hello,
I'm also growing a Coccinea from cutting: Here's what I did:
I cut it, and cut all leaves down to half size.
Then I put it in a cup with rooting hormone.
After a while, roots began to form out of the base of the cutting.
After the roots formed, I mixed up a pot of loose material (peat, orchid bark, and perlite) and put it in there.
I made sure to water it, and kept it in a terrarium with high humidity.
One bit of advice: The roots will form wherever the "inside" of the plant is exposed to the water. When I did my cutting, I only did a straight cut. I now wish I had done a diagonal cut, and perhaps done some slits up the sides. This would mean a greater surface area for roots to form, and allow for more water absorption.
It appears to be doing well, and actually is doing something unexpected:
I assumed it would start creating shoots out from the base of the leaves. This is what appeared to happen in the cutting instructions I saw. What mine did, is take root, then continue growing out of the "top" the way it was before. Is this common? I thought the growing leaves would suffer too much trauma to continue growing.
As it stands now, it has only made a couples leaves, it is still slow going for this cutting. I keep it in a very warm and very humid terrarium, but it is still slowly gowing. Oh well, it is a pretty large cutting, so this is to be expected I suppose.
---Lane