Water iris flowers with blue-violet and green leaves that are tinged with purple at the base in early spring. It should be grown submerged in a few inches of water in the shores of lakes or on moist soil.
Iris x robust 'Gerald Darby' is a cultivar of aquatic iris which is known for its attractive purple-blue color of the flowers and the variegated foliage of purple. This hybrid form a group of narrow leaves, in the form of green sword. The leaves, in spring, take a purple color at the base, which vanishes by the summer. Between June and July, from blacks-purple stalks, sprouting 2-3 violet-blue flowers. This has iris rhizomes creeping (poisonous) to slow growth. It should be grown in full sun or partial shade location of land to be neutral to slightly acidic, surrounded by a few centimeters of water on the shores of lakes, streams or ponds. It reaches a maximum height of 60 cm and tolerates low temperatures, is resistant up to -30 ° C.
Iris x Robust is a hybrid derived from two Native Americans iris (Iris versicolor x Iris virginica).