Gerald Darby Iris

‘Gerald Darby’ is a clumping iris with blue-violet flowers, yellow signals, and foliage that carries a purple flush in spring before turning greener. The RHS accepts it as Iris × robusta ‘Gerald Darby’ and lists Iris versicolor ‘Gerald Darby’ as a synonym; the Chicago Botanic Garden describes a cross between Iris versicolor and Iris virginica. ## Seasonal display and placement The flowers open in late spring, with timing extending into early summer in some gardens. Published size estimates differ: the Chicago Botanic Garden describes flower stems 2–3 feet tall, while the [RHS profile](https://www.rhs.org.uk/plants/74641/iris-%C3%97-robusta-gerald-darby/details) lists a mature height of 1–1.5 metres and a spread of 0.1–0.5 metre. Use the upright clump near pond or stream margins, in moist borders, or for cut flowers. Its blue-violet blooms attract butterflies and birds. ## Growing conditions Plant in full sun or partial shade and provide moist to wet, humus-rich soil. This is a useful choice for a rain garden edge or consistently damp border, rather than a dry site. The Chicago Botanic Garden records the cultivar as hardy in USDA Zones 4–9. ## Maintenance Remove spent flower stems and dying leaves. Divide congested rhizomes in late spring to maintain healthy clumps, and watch for slugs, snails, thrips, and iris diseases.