I can't be sure, but it looks more like a Louisiana Iris to me.

Wow, your garden is so pretty. I love the lime-green around the tree. Whatever it is, it is a lovely iris.

I would say it's a Louisiana also.

Siberian leaves are normally slender, LAs are wider. Hold a leaf up with the sun behind it, and see if you see lines across it. Those are common in water irises, and would denote it's a LA instead of a sib.

I have this and it is a Louisiana,its name is sea wisp.

Pat