It is a small, more or less prostrate shrub with aromatic, elliptic to oblong leaves and red flowers.

Prostanthera calycina is a more or less prostrate shrub that typically grows to a height of about 0.5 m (1 ft 8 in) and has more or less cylindrical, hairy branches.

[6][7] West coast mintbush is only known from the Eyre Peninsula in South Australia where it usually grows on limestone outcrops in mallee vegetation.

The main threats to the species include grazing, habitat fragmentation and road maintenance.

[5] This mintbush is easily propagated from cuttings or by grafting onto Prostanthera nivea and grows best in dry climates in well drained soil.