Prostanthera

Prostanthera, commonly known as mintbush or mint bush, is a genus of about 100 species of flowering plants in the mint family Lamiaceae, and all are endemic to Australia. Plants are usually shrubs, rarely trees with leaves in opposite pairs. The flowers are arranged in panicles in the leaf axils or on the ends of branchlets. The sepals are joined at the base with two lobes. The petals are usually blue to purple or white, joined in a tube with two "lips", the lower lip with three lobes and the upper lip with two lobes or notched.

Description

Plants in the genus Prostanthera are usually shrubs or subshrubs, rarely trees, with leaves arranged in opposite pairs. The flowers are arranged in panicles in leaf axils or on the ends of branchlets with bracts and bracteoles at the base. The sepals are joined at the base but with two lobes. The petals form a tube with two lips, the lower lip with three, usually spreading lobes and the upper lip with two lobes or a notch at the tip. The petal tube is bluish purple to white or more or less red. There are four stamens, the anthers often with a small appendage. The ovary has four lobes and the tip of the stigma has two branches.

Taxonomy

The genus Prostanthera was first formally described in 1806 by Jacques Labillardière in his book Novae Hollandiae Plantarum Specimen and the first species he described was Prostanthera lasianthos. The word is derived from the Greek for an appendage. Within the flowers are small spur-like appendages on the anthers.

Ecology

Prostanthera species are used as food plants by the larvae of hepialid moths of the genus Aenetus including A. eximia and A. ligniveren.

Uses

Mint bushes are cultivated as ornamentals and for essential oils and spices.

Species list

The following is a list of species accepted at the Australian Plant Census as at October 2025:Prostanthera albiflora B.J.Conn Prostanthera albohirta C.T.White Prostanthera althoferi B.J.Conn

* Prostanthera althoferi B.J.Conn subsp. althoferi
* Prostanthera althoferi subsp. longifolia B.J.Conn Prostanthera ammophila B.J.Conn Prostanthera arapilensis M.L.Williams, Drinnan & N.G.Walsh Prostanthera askania B.J.Conn – tranquility mint-bush Prostanthera aspalathoides A.Cunn. ex Benth. – scarlet mint-bushProstanthera athertoniana B.J.Conn & T.C.Wilson Prostanthera baxteri A.Cunn. ex Benth. Prostanthera behriana Schltdl. Prostanthera caerulea R.Br. – lilac mint-bushProstanthera calycina F.Muell. ex Benth. – west coast mint-bushProstanthera campbellii F.Muell. Prostanthera canaliculata F.Muell. Prostanthera carrickiana B.J.Conn – Carrick's mintbushProstanthera centralis B.J.Conn Prostanthera chlorantha F.Muell. ex Benth. – green mintbushProstanthera cineolifera R.T.Baker & H.G.Sm. – Singleton mint bushProstanthera clotteniana A.R.Bean Prostanthera collina Domin Prostanthera conniana T.C.Wilson Prostanthera crocodyloides T.C.Wilson Prostanthera cruciflora J.H.Willis Prostanthera cryptandroides A.Cunn. ex Benth. - Wollemi mint-bush
* Prostanthera cryptandroides A.Cunn. ex Benth. subsp. cryptandroides – Wollemi mint-bush
* Prostanthera cryptandroides subsp. euphrasioides B.J.Conn Prostanthera cuneata Benth. – alpine mint-bushProstanthera decussata F.Muell. – dense mintbushProstanthera densa A.A.Ham. – villous mint-bushProstanthera denticulata R.Br. – rough mint-bushProstanthera discolor R.T.Baker Prostanthera eckersleyana F.Muell. – crinkly mint-bushProstanthera elisabethae B.J.Conn & T.C.Wilson Prostanthera eungella B.J.Conn & K.M.Proft Prostanthera eurybioides F.Muell. – Monarto mint-bushProstanthera ferricola B.J.Conn & K.A.Sheph. Prostanthera florifera B.J.Conn – Gawler Ranges mintbushProstanthera galbraithiae B.J.Conn – Wellington mint-bushProstanthera gilesii Althofer ex B.J.Conn & T.C.Wilson Prostanthera granitica Maiden & Betche – granite mint-bushProstanthera grylloana F.Muell. Prostanthera hindii B.J.Conn Prostanthera hirtula F.Muell. ex Benth. Prostanthera howelliae Blakely Prostanthera incana A.Cunn. ex Benth. - velvet mint-bushProstanthera incisa R.Br. – cut-leaved mint-bushProstanthera incurvata B.J.Conn Prostanthera junonis B.J.Conn Prostanthera lanceolata Domin Prostanthera laricoides B.J.Conn Prostanthera lasianthos Labill. – Victorian Christmas bushProstanthera linearis R.Br. – narrow-leaved mint-bushProstanthera lithospermoides F.Muell. Prostanthera magnifica C.A.Gardner – magnificent mint-bushProstanthera makinsonii B.J.Conn & T.C.Wilson Prostanthera marifolia R.Br. – Seaforth mint-bushProstanthera megacalyx C.T.White & W.D.Francis Prostanthera melissifolia F.Muell. – balm mint-bushProstanthera monticola B.J.Conn – monkey mint-bush, buffalo mint-bushProstanthera mulliganensis B.J.Conn & T.C.Wilson Prostanthera nanophylla B.J.Conn Prostanthera nivea A.Cunn. ex Benth. – snowy mint-bush
* Prostanthera nivea var. induta Benth.
* Prostanthera nivea A.Cunn. ex Benth. var. nivea Prostanthera nudula J.M.Black ex E.L.Robertson Prostanthera oleoides T.C.Wilson & B.J.Conn Prostanthera ovalifolia R.Br. – mint bushProstanthera palustris B.J.Conn Prostanthera parvifolia Domin Prostanthera patens B.J.Conn Prostanthera pedicellata B.J.Conn Prostanthera petraea B.J.Conn Prostanthera petrophila B.J.Conn Prostanthera phylicifolia F.Muell. – spiked mint-bushProstanthera porcata B.J.Conn Prostanthera prostantheroides T.C.Wilson, M.J.Henwood & B.J.Conn Prostanthera prunelloides R.Br. Prostanthera rhombea R.Br. - sparkling mint-bushProstanthera ringens Benth. – gaping mint-bushProstanthera rotundifolia R.Br. – round-leaf mint-bushProstanthera rugosa A.Cunn. ex Benth. Prostanthera saxicola R.Br.
* Prostanthera saxicola var. bracteolata J.H.Willis
* Prostanthera saxicola var. major Benth.
* Prostanthera saxicola var. montana A.A.Ham.
* Prostanthera saxicola R.Br. var. saxicola Prostanthera schultzii F.Muell. ex Tate Prostanthera scutata C.A.Gardner Prostanthera scutellarioides Briq. Prostanthera sejuncta M.L.Williams, Drinnan & N.G.Walsh Prostanthera semiteres B.J.Conn
* Prostanthera semiteres subsp. intricata B.J.Conn
* Prostanthera semiteres B.J.Conn subsp. semiteres Prostanthera sericea B.J.Conn Prostanthera serpyllifolia Briq. – small-leaved mint-bush
* Prostanthera serpyllifolia subsp. microphylla B.J.Conn
* Prostanthera serpyllifolia Briq. subsp. serpyllifolia Prostanthera spathulata T.C.Wilson & B.J.Conn Prostanthera spinosa F.Muell. – spiny mint-bushProstanthera splendens B.J.Conn Prostanthera staurophylla F.Muell. Prostanthera stenophylla B.J.Conn Prostanthera striatiflora F.Muell. Prostanthera stricta R.T.Baker – Mount Vincent mint-bushProstanthera suborbicularis C.T.White & W.D.Francis Prostanthera tallowa B.J.Conn & T.C.Wilson Prostanthera teretifolia Maiden & Betche – turpentine mint-bushProstanthera tozerana B.J.Conn & T.C.Wilson Prostanthera tysoniana B.J.Conn Prostanthera verticillaris B.J.Conn Prostanthera violacea R.Br. – violet mint-bushProstanthera walteri F.Muell. – blotchy mint-bushProstanthera wilkieana F.Muell.