What I did in this situation was to dig them in the fall and pot and kept them in my basement.....didn't water them through the winter.....planted them out the next Spring when day and night temps were above 50* which is usually end of April here. I did this until they were too big and heavy for me to repot and bring in. Just didn't want to lose them. This is the 3rd year for mine left outside for winter and I mulch and leave out for the winter. They are doing great. This is 3rd year... 2 month (for this year) growth now for Illinois.[IMG]
They do grow better in the ground than in a pot and less chance of root rot.
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