Long story short I've wound up overwintering some blue potato plants. They're set up in tall containers (aka trash cans) for mounding and all of that, they go outside whenever its warm enough, windows/cfls/grow lights indoors when they can't, yadda yadda yadda.

I've heard about how big these things can get. What I'd like to know is how well they'll fare to being kept pruned to bush/houseplant size after they reach the tops of the cans.

I know the less bush they have up top the less energy they'll have to send down for tuber growth, and I'm not expecting baking sized potatoes out of these things right now (I'll expect those this summer).

Questions are:

1) Will they live if kept pruned back relatively small (I'm assuming it will)

2) Will I have any chances of getting any sized potatoes out of them when I'm done (to use as seed for the spring)?