|Bearded Irises have thick surface rhizomes, giving rise to fans of sword-shaped, usually broad green leaves, and simple or branched flower stems. Most bear multiple flowers per stem. The flowers have well-developed standards and falls, with a prominent "beard" of white or colored hairs in the center of each fall petal. Avoid high nitrogen fertilizer. Keep mulches away from leaves and rhizomes. Taller cultivars may require ataking. Water moderately during growth periods; keep dry while dormant. Tall bearded irises grow to 27 inches and produce flowers, 4 to 8 inches across, in midseason.