After the plant is finished blooming, do I cut the flower stem?
Certified GKH Gardening Expert
You can if you would like, but it isn't completely necessary. There are times when you would normally prune the plant if you wanted to wait until then. If you just want to rid of the dead blooms, then it is ok to cut these off.
Here is an article for more information on the care of these plants: https://www.gardeningknowhow.com/ornamental/flowers/plumeria/growing-plumeria.htm