Each segment a plant, each plant a forest. If you wanted a simple challenge, you could even quarter each segment and grow it from literal cuttings into plants.

I would find one long line from the roots to the end and keep that in this pot, and then cut and root everything that is growing off that main line.

Cactusmcharris, yes, I definitely will attempt to root all of those cuttings so that I can put the plants into a pot with a proper trellis. This is exciting!

Shapirolh, that sounds like a great idea. I will cut and attempt to root everything I can from that main line this next weekend. Just a question though, am I leaving that long line in this pot so that I can use for continuous growth of new cuttings in the future?

It's hard to tell how big that pot is, but I would attempt to retrain that mainline back into a more typical dragonfruit configuration. One long stem, then top it off and let it branch from the top to start producing fruit!

If the pot is big enough, leave it in there, stake or trellis that main line up, then if it's as tall as you want it (4-6-feet) cut it off and let it branch from there.

Shapirolh, the pot is too small I think. Once I've cut off the cuttings and this main line heals, I'll move it to a bigger pot to be trellised. I went outside to take a better pic so you could guesstimate the size, and luckily my lazy cat was napping right next to it- see size comparison. Thank you so much for your and everyone's advice! The Internet is great!

Well, today I went and was going to start cutting, then I noticed that the planted segment seems really dry and almost dead. I wonder if I can still replant this and start training it on its trellis with this damaged-looking segment.. gosh, what a bummer. The rest of the plant and segments seem healthy enough, it is just the part that is potted that looks dead.

It could be dried out, but sometimes it is corking - a natural process when the older stems brown up. When you take it out of the pot, you may be able to see better and see if there are any roots.

I would think that if dead, any segment should grow, these are such vigorous growers. I think in your climate you could grow them in ground? - that may be best if you can, they need a long warm growing season to produce fruit.

See and read -here-

and -also here-

and little about container growing-on this page-

and see this potted 'farm' -click on me-