I stake all my plumeria that are in the ground, some 30 plants. Perhaps, Jason, plumeria "trunks" will crack when winds bend them back and forth. Plumeria are really top-heavy plants when fully leafed out. I'm simply guessing at the cause. In 30 yr. of growing 1000's of them, as far as I know, I've never seen air-roots on any of my plants. I do not believe growth rate is a factor.
