Iris rhizomes ("bulbs") for sale, $1 each or $10 for a dozen. Tall bicolor bearded iris, burgundy & beige (see photo). Bloom in late May. Draught-tolerant. In my upper south hill yard with partial afternoon shade, these grow without supplemental water in sun and part sun so may be suitable for xeriscape. These grow about 30" tall and are evergreen, and can add formal structure to a garden (see photo). Many available.
Fall, after the summer heat and before the ground freezes, is the optimal time to plant iris.