It sounds like a handy, natural propagation trick, but tried-and-tested methods are more reliable
The problem
Taking cuttings is one of the most satisfying things you can do as a plant owner, but most people lack confidence. Stems sit in water for weeks doing nothing, or collapse in soil before roots appear. So when a hack promises to speed things up using nothing more than a raw potato, news travels fast.
The hack
The potato is supposed to keep the cutting hydrated and release nutrients as it breaks down, giving the stem everything it needs to form roots before it has to fend for itself. Some videos claim that potatoes contain salicylic acid, which encourages rooting.