Height. It’s height that makes the stems get girthy and also increases the leaf size at the growing tips. Height does not equate to length - it’s the vertical climb that’s important and of course, time.
In habitat the vines go straight up for the canopy to find more light & by the time they get there, they have leaves 3 feet long and quite thick stems - up to around 2” diameter and as much as forty feet in height.
The more vertical height they ascend, the more robust they become.
Saw a very impressive one in a hydroponic store once - it was an everyday
Epipremnum aureum Golden Queen and in its pot, it had the standard size juvenile leaf form.
But they had the vine growing from the pot across an indoor pond & then it wound up a column to the ceiling. The stem on it was quite thick but I paid it little attention - the leaves were what caught my eye.
The vine section in the pond water was leafless but where it exited and started climbing, the leaves were larger and every leaf was a little larger than the one below it.
At the top of the column, at least 12’ off the floor, the leaves were about double the width of my palms (which are quite wide for a female) and if memory serves me, a good 8” or maybe a little more in length.
They rarely watered the pot though they didn’t let it go bone dry - but the vine had its roots into the pond and was pretty much growing hydroponically despite technically being in a terrestrial pot.
I politely asked for and was pleased to receive a tip cutting with those huge leaves and the growth it produced, as I was warned it would be, was the regular size we see all the time. So disappointing.

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