I am sorry for this delayed reply to your gardening question. The spring rush has brought a deluge of questions and we are working hard to catch up!
That growth habit is common for plumeria. Whenever you cut a shoot back it will often resprout but not necessarily enough to improve the fullness of the plant. The following web site offer more info on how to grow plumerias:
Thanks for the question. Best wishes for a wonderful gardening season. Please stop in again soon!
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