Thanks Jonna, for the info. i have 3 sizes of trellises but the smallest might be too short. I just got fascinated with this plant. It just so happen a co-worker of mine trimmed her dragon fruit and gave me several cuttings.
I bought a little plant earlier this year (Haley's comet) and it is growing so fast, it is kind of scary. Just 2 segments when I bought it:
Here it is now just a few months after:
Glad to know they bloom on the bottom of an arched branch. I was asking at a different forum if it is a good idea to trim it but no one seems to know anything about dragon fruit in that forum.