jeg - good idea! I did that with edible ginger that I grow in a big pot year-round. That one organic rhizome from 3 years ago keeps me well-supplied.
Unfortunately, my 'Sangre' developed some sort of blight. It was my third choice on an order that I had placed months in advance. First choice was unavailable at shipping time, second choice ran out so I had to settle. Have learned my lesson but, this year was a learning year. I only got 1 1/2 dozen golf ball-sized 'Sangre' potatoes. 'German Butterball' tried to resist the blight and hung in there a little longer but the foliage finally succumbed to blight. I did get a little better harvest but not what I had hoped for. We had a hot, humid, dry first half of summer and that's when the blight developed. I would like to try 'German Butterball' again but definitely want a more disease-resistant red potato.