I think cutting the plants short is a preference. The benefit is you get more plants/branches and you can see the blooms. My hubby like them tall so he doesn't get poked everytime he trims our bushes. It is true also that my plummies that get full sun blooms all the time, so maybe yours are reaching for the sun.
Mine was leggy since it was over 3 feet tall, thin and with 2 6 inches tips only before I cut it up. There are also really varieties that grow tall first before they bloom. I have the 2 noid with pink blooms (possibly Miami Rose) and they are 7 to 8 feet tall both with 2 tips (each tip over 2 feet long). These are candidate for cutting up after the blooms because I can't enjoy the blooms. But I'm waiting for it to be multi-tipped so I have instant tree when I root them.
