This rhizomatous perennial has an upright clumping habit with large flax-like sword-shaped mid-green leaves. The white iris-like flowers appear in clusters on tall stems above the foliage during spring. 

Hardiness zones 9 to 11 

Dietes robinsoniana is naturally found on Lord Howe Island growing in sub-tropical conditions in well drained moist soils. It prefers a oprn sunny to semi-shaded position and is drought and frost tender but salt tolerant.

The Wedding Lily is the largest of the Dietes genus and is grown in parks and gardens along borders or mass planted. It is used around a water feature or in a large rock garden where it will establish in 2 to 3 years from division. It is also grown as a container or planter box specimen and in frost prone regions it is grown under glass. ID 1390

Note:
This plant is regarded as a weed in southern USA as it self-sows readily.

Dietes (di-EE-tees) robinsoniana (robin-SO-ne-ar-na)

Iridaceae (eye-rid-AY-see-ee)
Iris Family