Tire stack..... Start growing in a tire or right on the ground. As soon as it's taller than the next available tire take that tire place it on the stack and bury the plant until there's just a couple of leaves above ground. Everything you buried be gentle will root out and become space for more spuds. When it grows up taller than another tire rinse and repeat until you have a stack of tires when you're ready to harvest just start knocking the tires over one by one. Works well to line them with plastic as well if you can
I've recently heard of some people living near the coast, carrying on an old local tradition of simply growing potatoes in seaweed instead of soil, adding a natural salty taste to them.
Can confirm. Started potatoes in a grow-bag last year, did another round this year. The bag doesn't hold a ton of soil, but it was apparently enough to turn 5 seed potatoes into a few kilos of harvest