It is an erect, compact shrub with egg-shaped leaves with the narrower end towards the base, and pale lavender to almost white flowers with purple blotches.

The sepals are green, usually tinged with purple and form a tube 2.5–3 mm (0.098–0.118 in) wide with two lobes.

[2][3][4] Prostanthera cuneata was first formally described in 1848 by botanist George Bentham in de Candolle's treatise Prodromus Systematis Naturalis Regni Vegetabilis.

[7] Alpine mint bush occurs in alpine and subalpine closed heath and shrubland in granite-based soils in New South Wales and Victoria, often in association with snow gums (Eucalyptus pauciflora).

In cultivation this plant has gained the Royal Horticultural Society's Award of Garden Merit.