blue flax-lily

Dianella caerulea is a strappy herbaceous fruit bearing plant to about 1 metre (3 ft) high, with a thick spreading rhizome under the ground. The bright green leaves have straight or toothed margins, and may reach 75 cm (30 in) in length and 0.3-2.5 cm wide. The small (1-1.6 cm diameter) flowers bloom in spring and summer (August to January); the perianth is pale to a dark blue, or green-blue, and the anthers at the centre are yellowy brown. These are followed by small roughly spherical indigo-coloured berries which range from about 0.7 to 1.2 cm (0.3-0.5 in) in diameter. These fruit are edible.

The plant is distributed through a range in Australian Capital Territory, Victoria, New South Wales, Tasmania, and Queensland. It occurs in a wide range of habitats, from coastal heathland and even sand dunes. Dianella caerulea has been introduced to Oahu, Hawaii.

Believed to have been first propagated in England in 1783, Dianella caerulea is commonly cultivated in gardens, and is sometimes seen as a low-hedging plant in public spaces and amenities plantings. It is very hardy and long-lived, and suitable for rockeries. It is tolerant of poor drainage and responds well to extra moisture. Plants attract fruit-eating birds and butterflies in garden settings. The smaller denser forms in particular have potential for small gardens.