Patersonia sericea

Patersonia sericea, commonly known as the purple flag, native iris, silky purple flag or native flag is a species of plant in the iris family Iridaceae which is endemic to eastern Australia. It is relatively easy to cultivate, and even the type specimen provided to the taxonomist, Robert Brown was "...furnished us by Messrs. Lee and Kennedy, of Hammersmith, [West London] who received the seeds, from which they raised it, from Port Jackson".

The purple flag is a densely-tufted perennial herb growing to a height of about 60 cm. It has stiff, erect grass-like green leaves 15–60 cm long and 2–6 mm wide, that are finely stiated, glabrous except for the margins which have fine hairs and near the base which is covered with short white hairs. The flower stalk is 3–55 cm long and the petals (strictly outer tepals) are roughly oval in shape, 20–30 mm long, 15–25 mm wide and blue-violet in colour. The flowers appear in spring and summer and each lasts for less than a day.

Patersonia sericea is an attractive species for the garden in a well drained, sunny or semi-shaded position with assured moisture. The species is tolerant of at least moderate frost.

Propagation is relatively easy from seed which does not require any special pre-treatment. Division of large plants is also a successful method.