Prasophyllum

Prasophyllum, commonly known as leek orchids, is a genus of about 140 species of flowering plants in the orchid family, Orchidaceae and is found in Australia and New Zealand. The Australian species are found in all states but have not been recorded in the Northern Territory. The common name arises from their having a hollow, leek- or onion-like leaf. Some species only flower after summer fires and have flowers similar to those of Xanthorrhoea which flower at the same time, suggesting that they employ the same pollinating insects. Leek orchids are similar to those in the genus Genoplesium except that the free part of the leaf is cylindrical (flat in Genoplesium) and the labellum has a solid (rather than flexible) connection to the column. They range in size from the little laughing leek orchid (P. gracile) at about 15 cm (6 in) to the king leek orchid (P. regium) which grows up to 2 m (80 in) tall....read more on Wikipedia.