I am not sure about the specifics you inquired about since I"m not sure about the actual stage your plants are in, but I too had some plants that flowered and I was pinching off flowers and part of the tops broke off too far...So I continued to take the flowers off the top and put (stuck down) the rest into a pot with another plant, giving it no particular attention. It has grown well and filled in and is like a whole new plant. I felt like these rooted as well as like a choleus would.

I had never tried that before, but am glad to know it works, so that this year I can take cuttings before any cold weather comes and start new plants for the greenhouse.

IN FACT, I'm going to go do that now!!!