The flowers are scented, green, reddish-brown or red and as with others in the genus, are inverted so that the labellum is above the column rather than below it.

[2][3] Prasophyllum frenchii was first formally described in 1889 by Ferdinand von Mueller and the description was published in The Victorian Naturalist from a specimen collected by "G.

[1][4] The specific epithet (frenchii) "is named after the youthful collector, who has filially inherited from one of the principal founders of the Field-Naturalists' Club his ardour for forming, by searches of his own, zoologic and phytologic collections, and instituting observations thereon".

[4] The maroon leek orchid is widespread but rare, occurring from south-eastern Victoria to the south-east of South Australia.

The main threats to the population are grazing, weed invasion and inappropriate fire regimes.