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Synonyms: Plectranthus graveolens R.Br. APNI*

Description: Erect, openly branched suffrutescent shrub to 1 m high, with distinctively glandular leaves and branches, producing a strong medicinal or sometimes sweet smell when touched and crushed. Coloured multicellular sessile glands up to 8-celled and orange. Does not form a distinctive tuber. Branches with sparse, patent, non-glandular trichomes (distinctively longer and antrorse at nodes), densely distributed glandular trichomes, and sparse coloured multicellular sessile glands.

Leaves discolorous; petiole 0.25 to 0.7 length of lamina; lamina ovate to very broadly ovate, 15–110 mm long, 15–80 mm wide; apex acute to obtuse, base subcordate to broadly cuneate, margin evenly dentate or crenate with 10–19 (–21) pairs of teeth; upper and lower surface with densely distributed hairs and glandular hairs, veins impressed above and raised below, sessile multicellular glands more densely distributed on lower surface than upper surface.

Inflorescence 150–250 mm long, consisting of up to 5 racemose branches, verticillasters 10–15-flowered. Pedicel 2–4.5 mm long. Calyx 1.6–3 mm long. Corolla blue to purple-blue, 8–14 mm long; tube 4.5–5.6 mm long, curved downwards at an angle of 90°–130°. Stamen slightly inserted to exserted past lower lobe, pollen orange. Style extending just past stamen and lower lobe.

Fruiting calyx accrescent, 4–5 mm long. Mericarp glossy dark-brown (sometimes also reddish), subcircular or ovate-circular in outline, 0.8–1 mm long, 0.75–0.95 mm wide.

Flower Photo D. Hardin

Other photo Photo D. Hardin

Flowering: between August and May.

Distribution and occurrence: Found from Hunter valley New South Wales, north to the Rockhampton area of Queensland.

Grows on sides of cliffs and exposed ledges or on steep rocky slopes in a variety of soils, commonly volcanic derived.
NSW subdivisions: NC, NT, NWS
Other Australian states: Qld

AVH map***

Coleus graveolens is a problematic taxon, frequently being confused with other robust and shrubby Australian Coleusspecies, especially in New South Wales. Corresponding to its distinctively glandular nature, when so much as any plant part is touched, it emits a heavy scent that could be described as medicinal or sweet. The highly glandular nature sets it apart from numerous other forms found across New South Wales, which appear to be either hybrids or undescribed species based on currently unpublished, ongoing taxonomic research using molecular tools. This species cooccurs with C. australis and C. alloplectus, between which individuals bearing intermediate morphology have been observed.