August is probably best for Iris. And you can get good "end of season" sales from your garden nursery. I got most of my bearded types for $1 or $2 per pot from those sales.
Most were mislabeled though.
The smaller rust/yellow ones were just marked yellow.
Last one is a Siberian Iris that we got from Veseys mail order. It came in a multi pack so I don't know it's catalog name.
I'll dig out my old catalogs and try to find the name for you.