Sounds great. Do you have a greenhouse where you can plant them out earlier ? Asking since it appear to be that you are very early. Normally, we can grow a full sized plant from tuber in 8 weeks. Your area is probably 13 weeks or more from last frost ?? !!

It's probably early. It will be two to three weeks before I pot them in sphagnum. I use flourescent light fixtures. By mid april (???) they are outside in a northern exposure getting acclimated and where they can be moved into my garage quickly if need be.

bmchan,

I also but pots of tubers in my basement for the first time this winter. I'm not sure what to do with them. When you bring them in the house do you water them right away?

I may be too early, but in mid march to be safe - take them out and dip them in water for a moment and put them at house temp. In a week, I wet them again. By the second weekend (or 3 weeks) they are showing pink stem nobs on the top.

Bury them up to their shoulders in sphagnum peat moss (the stringy stuff). This can be done in a large flat with multiple tubers. This is temporary until the roots show. Keep the sphagnum moss wet. When the roots are 1/4" long, put them in their own pots and gradually bury them in Promix as the stems develop. They should be 1" deep by the time you plant them.

Note: this timing assumes that you can grow them in strong (not direct sunlight) light. I use flourescents. I grow mine in window boxes and containers only. Growing them in flower beds invites grubs etc.