I got several of those plants and they all are trying to play giraffe. (just growing up and up and up)
I keep wanting to try grafting onto--into a caudex to get more branches. Someone over in the Yahoo group drills holes in a caudex and sticks a branch in and it takes sometimes. She said if it doesn't grow, you just have a hole in your caudex.
Hum, those pesky unwanted rootstock branches could be used to graft a bit of the top that you want--??
