This is my first time with Dahlias. I bought 2 and planted them in containers. They came up and blossomed (but not very good flowers). Then they seemed to die on me, actually I thought I killed it. Thought it was the heat so I just went ahead and cut them back to the ground. Well, both of the them are growing and nice foliage. Since it didn't die on me like I thought, I'm going to keep them over winter. Any suggestions on how to keep them? I do have a basement and it's finished, so I don't know if they need to be winter out in the garage instead. Any assistance is greatly appreciated. THANKS!