Dietes robinsoniana, the Lord Howe Wedding Lily is only found naturally growing at Lord Howe Island

Lord Howe Island

Lord Howe Island is an irregularly crescent-shaped volcanic remnant in the Tasman Sea between Australia and New Zealand, directly east of mainland Port Macquarie, and about from Norfolk Island. The island is about 11 km long and between 2.8 km and 0.6 km wide with an area of...

. It grows on cliff faces, often in exposed situations. Found also on forest margins and the tops of Mount Gower

Mount Gower

Mount Gower dominates the southern tip of Lord Howe Island and has its peak at 875 metres .Average climbing time to Mount Gower's summit is 8 – 10 hours. The path is rope-assisted and rated as one of the world's best one-day hikes...

 and Mount Lidgbird

Mount Lidgbird

Mount Lidgbird is located in the southern section of Lord Howe Island, just north of Mount Gower, and has its peak at 777 metres ....

 and behind the beaches on Lord Howe Island.

This is the largest plant in the Dietes

Dietes

Dietes is a genus of rhizomatous plants of the family Iridaceae. Common names include Fortnight lily, African iris, Morea or Moraea iris, Japanese iris and Butterfly iris, each of which may be used differently in different regions for one or more of the four species within the genus.Most species...

genus. It does not tolerate cold temperatures.
An uncommon plant, though it may be locally abundant in certain sites. Growing up to 1.5 metres tall, the leaves are sword-shaped or linear, 4 to 7 cm wide. Flowering occurs from September to December. The flowers are white with yellow, lasting for one day only.

• Link to a flower photo:

Flat triangular seeds form in a roundish shaped capsule, 3 to 4 cm long. The black seeds are around 10 mm long.