It is a tufted perennial herb with sword-shaped leaves and blue-violet flowers.

Patersonia lanata is a tufted perennial herb with sword-shaped leaves 150–400 mm (5.9–15.7 in) long, 2–7 mm (0.079–0.276 in) wide and is glabrous apart from woolly hairs near the edges of the leaf base.

[3][4] Patersonia lanata was first formally described in 1810 by Robert Brown in his Prodromus Florae Novae Hollandiae et Insulae Van Diemen.

[5][6] The specific epithet (lanata) means "woolly", referring to the edges of the leaves, the scape, bracts and ovary.

[7] In 1986, David Alan Cooke described two forms of Patersonia lanata and the names are accepted by the Australian Plant Census: Woolly patersonia grows in heath on the coastal plain of southern Western Australia between Two Peoples Bay and Israelite Bay in the Esperance Plains, Jarrah Forest and Mallee biogeographic regions.