Yes you can grow your Peonies in large containers-They will grow very well and flower. One thing to keep in mind is that you do not want them to start growing to early in the spring -so that a late frost kills off the buds or even the whole root. What I do here in MN zone 4 is put the plants in a two to three gallon can in the spring. when winter comes they have nice large healthy root hairs and a good root system. I cover the pots with three inches of straw and cover the straw with plastics. I do not uncover until April 10. I have had very good results- on the average over wintering 50-200 plants a year. The plants have done better in the pots than in ground ( good soil makes the peony) P.S. when you over winter them try to put then in a shady spot or cover them with a old carpet or a old blanket. --------------------------------------------------------------------- To sign-off this list, send email to majordomo@mallorn.com with the message text UNSUBSCRIBE PERENNIALS