It has a single tubular, dark green leaf and up to eighty scented, yellow-green flowers with red or brown marking.

Prasophyllum hectorii is a terrestrial, perennial, deciduous, herb with an underground tuber and a single dark green to yellowish-green, tube-shaped, rush-like leaf which is usually taller than the flowering stem.

[2][3][4] The swamp leek orchid was first formally described in 1887 by John Buchanan who gave it the name Gastrodia hectori and published the description in Transactions and Proceedings of the New Zealand Institute.

[1][3] In 2005, Brian Molloy, David Jones and Mark Clements changed the name to Prasophyllum hectori in The Orchadian.

[2] The swamp leek orchid is classified as "at risk" and "declining" by the New Zealand Department of Conservation.