I'm in zone 6 and mine stay in the ground all year. They usually break ground in late March, bloom in late May and become dormant in late June. I dig them when they become dormant and remove the babies. I give these away and sometimes use them and some of the larger tubers to trade with. They need a well drained soil which I don't seem to have because I keep losing some of my bigger tubers. My tubers usually bloom when they reach a size of between 3 and 4 inches. I hope this helps.
Jim

Thanks Jim. I wonder if mine will even bloom then since I didn't put them in until late april/early may. Oh well, I may have to wait until next year...