Dianella is a monocot genus of flowering plants. They are commonly called flax lilies.
In the APG II system of plant classification, Dianella was placed in the family Hemerocallidaceae. When that system was replaced by APG III in 2009, Hemerocallidaceae was combined with two other families to form a larger version of Xanthorrhoeaceae.
Dianella ranges from Japan to India, thence south to Australia and New Zealand; also occurring on many Pacific Islands. About half of the species are native to Australia. Several species are grown for their attractive foliage and shiny, blue to purple berries. Estimates of the number of species range from 20 to more than 40. The type species for the genus is Dianella ensata, now a synonym of Dianella ensifolia.
Dianella is not well understood taxonomically and is in much need of revision. It is closely related to Thelionema and Herpolirion. Not all taxonomists recognize the genus. In one paper on the classification of Xanthorrhoeaceae, Dianella and six other genera were subsumed in the genus Phormium.
Long strappy leaves up to 1 m long
Range in colour from deep green, blue-green to pale green
Blue flowers in spring
3-petals & 3-sepals (or 6-petals to the casual observer)
Prominent yellow stamens
Borne in sprays on a stem, for most species above the leaves
Shiny blue to purple berries
5mm - 15mm diameter
Spherical to elongated
Shiny black seeds
Their habitat ranges from moist forests, dry woodland rainforests and coastal dunes