My second season with TPS so not an expert here
Read
http://tomatoville.com/showthread.php?t=13927&page=2 and
tatermater. p r o b o a r d s.com the thread called TPS in Bermuda (I does not let me link it for some reason put stars) I talk about what I did on those TPS selfed
They grow bigger but not as big as the 2nd year...I will tell you more in the fall
The dormancy will be 3 mo. for the short ones and near 5-7mo. for the rest. I do not have a root celllar so they were stored tat 45F in my basement until Feb/March that I moved them because some were sprouting. Unless they shrivel and go soft then they should be fine.
I recommend that you plant as deep as you can and the pot with at least 3/4 or 1 cubic feet of soil if my converter is accurate is 21-28 L.
Harvest when the plant totally die down. That way is the biggest taters and best to store over the winter. I will love to see how they continue growing in Finland, hopefully you both find a long storing/short season blue potato for your environment. I have more of Tom's Sampler I hope they cross and produce more interesting potatoes so far there is one that is catching my eye.. Amey X ...red stem and green leaves
no idea what it will produce!