Louisiana irises come in an amazing array of colors. 'Black Gamecock' is a beautiful deep purple, nearly black, and is very cold hardy. It is a reliable bloomer here even tho I am sure it would like more water in the dry summer months. Tho they thrive in their native bogs they do just as well in rich garden soil with average watering.
English irises are a bulbous species related to Dutch and Spanish irises. They are not native to England, but they do best in its cool mild climate, as well as here in the Pacific Northwest.
Each July brings blooms on the Japanese irises in my garden. I don't have many as our dry, sandy conditions are not to their liking, but a few rugged varieties manage to thrive for me. This is one, a large flowered variety in shades of lavender and blue with bright yellow-green darts at the heart.
Consider trying a few of these types if you're looking for irises with mid-summer impact. With the right combination of species and varieties you can have irises in bloom almost all year long.
