Last year I read about growing potatoes vertically in one of the gardening magazines I subscribe to and ever since then I have been obsessed with the idea!
While in Seattle in April, I came across a nonprofit selling used burlap sacks that were originally used by local coffee roasters to transport their beans. I bought three and two of which are now at home on our driveway with potatoes growing in them.
Apparently I was too late to purchase seed potatoes this year, but we had a few varieties of organic potatoes that had begun to sprout so we chopped them up and planted them.
As far as I can tell, you plant them in about six inches of soil, let them grow about six inches, cover them with dirt and repeat. Once the bag is full and the plants begin to flower you are ready to harvest.
We won't know how successful this experiment is until the end of the season, but I will continue to document the progress and success/failures along the way.