Q.Can I plant Iris rhizomes in spring?
I live in zone 5. Can I plant the Iris rhizomes in the spring? Will they flower in late spring or summer? I bought them late fall in 2014 and kept them in my garage.

I would examine the rhizomes to determine their health.
If they are dried, damaged or soft I would discard them.
They may or may not bloom the first year, but if they are healthy and viable they should began blooming by the second year.
https://www.gardeningknowhow.com/ornamental/bulbs/iris/iris-plant-care.htm