I have been using potato bags this year to grow some Charlotte potatoes. You can get those bags for a quid each in discounters-99p stores etc. They are a really good investment as you can reuse them, I would disinfect them after every growing season to avoid transmission of blight and Co.
I've managed to grow a solid 16 pounds of potatoes with just a few bags and minimum of work- a bit of potato fertilizer, a bit of hilling every now and then, no watering at all the rain alone was enough. The plants died due to blight but I still had a nice 'no bother' harvest. ☺