What you are describing sounds like what I call air-layering. You can do this to most any plant you want to reproduce. I take a limb or a piece of the vine and scratch it a little and stick this in the dirt and lay a brick or something on top of it. Once it roots, just cut the end that is going to the mother plant and wait. This will shock it a bit but it should grow enough roots to sustain itself in no time. Once you think it is rooted well enough, spade around the plant to cut lateral roots then wait a week or so. After this spade again and dig up the root ball leaving as much dirt as possible on the ball then transplant. Helps to cut the top back some to balance the root to top ratio some. What I described was the best way to do it. Personally, I'll leave out some of the steps and still have good luck.
