Answer: You take a chance when you uproot flowering plants but since you don't have a choice, here's what to do: Cut off the flowering stalks but leave the foliage alone. Dig each plant with as much of the root system attached as possible and set them in pots or other nursery containers to keep the roots from being exposed to too much air and yet allowing them access to fresh air. For this reason, plastic bags are not a good choice. If you're not moving very far away, and if you can replant them within a few hours of digging, you could set them into a cardboard box and then shovel some soil over the roots to keep them from drying out. If you're moving a distance away or you won't be able to transplant them for days or week, it would be better to transplant them into nursery containers or plastic pots.
Irises grow from elongated rhizomes. You'll find some pencil thick sized roots going straight down from the rhizomes, usually 6-12" deep. Try using a garden fork to lift the rhizomes, retaining as many of the roots as possible. Glads grow from corms that look like flat bulbs. Some corms will have little offsets attached so try not to damage them when you dig. The roots will be directly below the corm so dig down 6-8" to get as much of the roots as possible.
Both irises and glads need to have their foliage attached for as long as possible because the leaves feed the underground storage organs. So, even if the leaves begin to wither and die, leave them alone so the corms or rhizomes can get as much benefit as possible from the leaves.
Be sure to water well after replanting. By next spring the plants should be just fine.
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