Let us know the type of iris you are referring to - bearded, siberian, etc.
I did not plant them. They were here when we purchased the house 2.5 years ago. I believe they are bearded irises. They stand 3-4 feet tall and are deep purple with a bottom petal.
That sounds like bearded.
They do best transplanted in late summer through early fall so it's getting a little late.
We would probably go ahead though (maybe just do half, and the rest in the later summer) as it has become hard to say what the weather will do.
Transplant to full sun and into good soil amended with Leaf-Gro or compost that drains well. Keep them moist until the ground freezes.
They might not flower next year.