I have been growing my potatoes in a metal can. I have done this for a couple of years. The only problem is the metal can really heats up which is good and bad. It is good when we aren't having a warm summer but in the heat the plant really wilts. So I really have to water a lot this summer as it has been quite warm. The can has drainage holes in the bottom .
When we visited the Story Garden at Hovander Park they had a couple of potato plants in plastic garbage cans. I think I might do the plastic version.
Mavis at 100 dollars a Month is doing different versions of potato towers in straw and dirt. She has been posting her progress.