These were dangling from ONE potato plant. I'm plenty satisfied with this amount of yield considering each "plant" started as about a quarter piece of a single potato. These were purchased from my local Sprouts market (grocer).
I also bought purple potatoes and while they sprouted terrifically ABOVE ground, under ground the spuds maxed around the size of a pencil eraser (the kind you stick on the end of a pencil). VERY pathetic.