I had to dig up my iris because of construction where I had them. I live in Nebraska & the ground is frozen now. Whats the best way to keep them till Spring- I Also wonder about Day lillies I dug up.

Depending how many you have. A tote box or a plastic coffee container and add some glossy magazine paper. Crinkled up on top of the plants. The plants should fill the bottom of the container no more than two deep. Put the top on and keep them in the basement or a cool place that does not freeze.

Corms? Do you mean rhizomes?

Whatever.