About Iris douglasiana Herb.
Iris douglasiana Herb. is a beardless iris that belongs to subgenus Limniris, series Californicae. It grows from a rhizome that is usually less than 1 centimeter in diameter. Its leaves are roughly 2 centimeters (0.79 in) wide, and can reach up to 1 meter (3 ft) in length. Leaf color varies from yellow to dark green, and leaf bases have a more reddish appearance. The plant flowers from April to June; blooms are most commonly purplish-blue, but white or yellow flowers occasionally occur. Each flower stem holds 2 or 3 flowers, and stems vary in height between 15 and 80 centimeters (5.9–31.5 in). After flowering, blooms develop into seed capsules that can hold up to 80 seeds each. In the wild, Iris douglasiana grows along mainland coastal areas, from southern Oregon to central California. It prefers sunny locations, and is most often found in grasslands, with occasional occurrences in forests. It tolerates a wide range of soil types, and can spread quickly following ecological disturbances. Iris douglasiana is commonly cultivated both within its native range and in regions outside its native distribution. It has received the Royal Horticultural Society's Award of Garden Merit, which confirms it is suitable for garden growth in the United Kingdom. New plants can be propagated either from seed, or by dividing rhizome-connected growth. If left unmanaged, the irises will spread in their immediate area via both propagation methods. Iris douglasiana can be infected by the moth larvae of two taxa: Macronoctua onusta (the iris borer) and Amphipoea americana var. pacifica.
