Answer: All types of Plumeria will branch at flowering points. Usually this results in three branches. This is especially useful information for those new to plumeria growing who are watching their new cutting go straight for the ceiling as one slender stick. The temptation is to pinch the end to promote branching. However, pinching the end in this case will inhibit the emergence of flowers and possibly reduce branching overall. In fact, if the Plumeria being pinched is a variety that likes to sprawl it will often just try to send out a single new branch to continue in the direction it was growing before it was pinched. This behavior defeats the purpose for pinching it, and can result in an uglier plant rather than the increase in attractiveness desired. One can save themselves some frustration by researching what kind of growth characteristics a plant has before purchasing it.
If you are still interesting in the process of air layering, here's an excellent page, complete with sketches to guide you through the process:
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