Anna, if that plant has been rooted a good while (2-4 wks. perhaps), those roots will extend out and down a good ways. I don't know what size pot she has, but all plumeria (other than the compact growers) soon become top-heavy. I don't really think that burying the plant will do much good. I have to stake all my plants, all 80 of them, otherwise they would blow over whenever there is much wind. That's just the way it is with these trees. Just my opinion based on experience, you understand.
