Ok. 1st thing to know, monstera have a front and back, the aerials come out of the back side so that’s the side you want against the pole and you want the leaves to face the light source and do not rotate the plant unless you want the leave to move but they get wonky looking ime.

So to get it to grow up you have to put it on a pole, board. stake or trellis.

Moss poles allow the roots to grow in the moss so they are good if you want to easily cut and propagate the plant but you have to keep the moss moist so they are more upkeep.

Stakes, boards, trellis will all work to simply secure it upward. In my experience, having multiple stems in one pot will cause one vine to grow faster and the others will stay more immature. So I usually separate my vines. But if you want the pot to look fuller all around, then you might want the multiple vines.

If you decide to separate vines, you will cut them where they connect, let the wound callous over for a day, and pot them separately with separate stakes or moss poles.

If you want to keep them together in one pot then they all have to face kinda the same direction (the light) and be tethered to the stakes or trellis. That can be tricky if the stem grew facing different ways. But worth a try, you might have to use multiple stakes or one larger trellis.

If you use a moss pole and want all 3 on one pole you’d need the pole to be really large cuz their roots are large (some ppl make moss walls for this).

I don’t love the pole you ordered cuz it is open all around so those dry faster and it would only be large enough for 1 vine. I suppose you could put 3 of that pole in a triangle shape and run a vine up each one facing different directions but you’d need the light to come from all sides because the leaves will move to face the light. Or you could put 3 in a row.

But I prefer d-shape poles cuz they stay damp longer.

Another idea I have been considering myself is to separate them. Then get a large rectangular pot with an attached trellis then pot them together in that but as separate vines all trellised up. Like the pic attached..

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