A tufted or clumping perennial, to 60 cm high with ‘grassy’ leaves and a rhizome.
The Morning Iris is found in southern South Australia and Kangaroo Island. It also occurs in Victoria and Western Australia.
It grows in coastal heathland in southern Victoria, as well as coastal heath and shrublands over the rest of the range, often on sandy soil.
Orthrosanthus have simple linear (strappy) leaves. In this species, they are to 50 cm long by 0.6 cm wide, with a tough texture, mid green to dark green in colour, paler towards the base. Leaves emerge in a clustered fashion from the rhizome.
Orthrosanthus have iris-type flowers – with 6 tepals (3 petals and 3 sepals which are similar in appearance). Flowers are produced on a scape to 60 cm tall, with bracts enclosing developing flowers. Flowering clusters emerge from the bracts in up to 5, with each cluster having up to 8 flowers, with flowers about 40 mm across, mauve and white in colour, each lasting for only a day, but with flowers produced continuously through the season, mainly in spring and summer.
The fruit is a capsule, to 20 mm long with seeds about 2 mm in diameter.
This is a very hardy and attractive plant for informal rockeries or massed displays. The plants somewhat resemble Dianella spp. in form but not in flower.
Orthrosanthus multiflorus requires very little attention and flowers in winter through to early summer. It will grow in semi shade but will take full sun and may be used in coastal planting with some front-line shelter.
The flowers last only a day but are produced in such profusion that there is hardly a time during its flowering season that it is without a flower. Most people would find the butterfly and bee attracting qualities of this plant to be a bonus.
Plant in semi-shade on a well-drained soil with some moisture. It could be treated as a native bedding annual in some areas.
Propagation is by seed or division. Morning Iris is sometimes available in native plant nurseries and seed is also available from seed merchants.
The plant image was taken on Kangaroo Island October 2016.
Orthosanthus is a genus of about 9 species with 4 species endemic to Australia. There are no species in NSW.
This species likely regenerates after fire either through the seed bank or from the rhizome.
Orthrosanthus – from Ancient Greek – Orthros (ὄρθρος) meaning “sunrise”, “early morning” or “dawn” and anthos (Aνθος) meaning “flowers” referring to the flowering habit of the species where each flower lasts for about a morning period.
multiflorus – Latin meaning “many-flowered”.
This species listed as threatened (endangered) in Victoria. It is not considered to be at risk of extinction in the wild in South Australia or Western Australia.
Gardening with Angus – Orthosanthus multiflorus profile page https://www.gardeningwithangus.com.au/orthrosanthus-multiflorus-morning-iris/
Wrigley, J.W. & Fagg, M.I. (2001). Australian Native Plants – Propagation, cultivation and use in landscaping. 4th edition. New Holland Publishers, Pty. Ltd. Australia.
VICFlora – Flora of Victoria Online – Orthosanthus multiflorus profile page https://vicflora.rbg.vic.gov.au/flora/taxon/501138ad-65bc-4713-8cc7-37bafd7825e4