One of my favorite iris is still flowering in the garden now, Iris x pseudata ‘Chance Beauty’.  Iris x psuedatas are crosses between the European Iris pseudacorus and the Japanese Iris ensata.  Iris ‘Chance Beauty’ is the tallest of the group, topping out at 5′-6′ tall when grown in rich, moist soil. Unlike bearded German iris, this group can grow in up to 1′ of standing water.