I haven't done this but I would think that you could dig them, knock off the soil, trim foliage back to several inches, and spread them out on a tarp in you storage area. When your spring weather arrives break off some of the nice big rhizomes on the edges of the clumps and plant them. They will probably take another year to bloom but amending the bed will reward you. We all see dry brown starts in bags at the big box stores in the spring and with patience they will grow. I have had rhizomes survive laying on the surface over winter here in zone 5. Welcome to the iris forum. We will look forward your participation. Good luck
