Coleus australis
Common names
cockspur Flower
Biostatus
Native
Category
Vascular
Structural class
Herbs - Dicotyledons other than Composites
Flower colours
Blue, White
Detailed description
Perennial herb, all parts aromatic when bruised; stems greenish-orange, glandular puberulent, erect to spreading, ascending to 1 m, usually dying down to tuberous base after flowering. Petioles to 40 mm, hairy, channelled above. Leaf lamina 30-80 x 20-70 mm, green to yellow-green, broadly ovate, membranous, puberulent (especially on veins), with orange glands on leaf undersides; base truncate to cuneate, apex acute; margins with up to 10 pairs of teeth. Inflorescence terminal, narrow, up to 200 mm long. Flowers in whorls (verticels), these 8-20-flowered. Calyx 2-lipped; lower lip with 4 triangular subequal teeth, upper lip suborbicular, mucronate; fruiting calyx with prominent raised vein net. Corolla 8-11 mm; slightly hairy and glandular outside, tube horizontal or declined, pale blue to whitish, uppe rlip 2.4-4 mm; lower lip 4-5.5 mm. Stamens in lower lip, anthers dark blue. Style included equal in legnth of longest stamen. Nutlets 0.8-1 mm, rounded, glossy dark brown.
Similar taxa
None - the distinctive tuberous root stock, uniformly green to yellow-green leaves, which when bruised give of a distinctive pungent yet subtly lemon scented smell, and pale blue to white flowers are not seen in any of the cultivated or naturalised Coleus / Plectranthus present in New Zealand. Coleus australis is very variable throughout its range but New Zealand plants seem to be closest to those found in Queensland.
Distribution
Indigenous. In New Zealand confined to the North Island, where it is known locally from Tangihua and Mimiwhanga in Northland, and from the Waikato near Kawhia Harbour (Pukenoi, Awaroa Valley, Pirorua Valley), and at Whenuakite, on the Coromandel Peninsula. Common in Eastern Australia, present also in the Hawaiian Islands, Rarotonga and the Australs (Raivavae, Tubuai).
Habitat
Coastal to lowland. Mainly on base rich rocks in regenerating or early successional forest. Often found as an emergent on rock outcrops. Occasionally found on slips.
Current conservation status
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2022-2023 using the New Zealand Threat Classification System (NZTCS) – more information about this can be found on the NZTCS website. This report includes replaces all previous NZTCS lists for vascular plants. Previous assessments can be found here.
- Conservation status of vascular plants in Aotearoa New Zealand, 2023. 2024. Peter J. de Lange, Jane Gosden, Shannel P. Courtney, Alexander J. Fergus, John W. Barkla, Sarah M. Beadel, Paul D. Champion, Rowan Hindmarsh-Walls, Troy Makan and Pascale Michel Department of Conservation. Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2023 | Non-resident Native – Coloniser | Qualifiers: SO
Threats
First recognised in the country in 1989, though it had been collected earlier and confused with other quite different naturalised species. Although uncommon this species seems to be holding its own, and possibly even actively increasing its range. It does not seem to be particularly palatable, and in the wild goats, sheep and even possums tend to avoid it. Although almost certainly indigenous this species will need to be watched as it can be invasive in gardens and may yet prove a problem in the wild.
Detailed taxonomy
Family
Synonyms
Plectranthus australis R.Br., Plectranthus parviflorus Willd.
Endemic taxon
No
Endemic genus
No
Endemic family
No
Ecology
Flowering
October - April
Fruiting
October - June
Propagation technique
Very easy from seed and stem cuttings. However, it can become rather invasive and on account of this is unlikely to prove popular in cultivation. It is rather drought tolerant and does well on a sunny rock wall though plants look their bets in partial shade with ample moisture. Some people find the peculiar scent of the plants foliage rather nauseating.
Other information
Etymology
australis: Southern
Chromosome number
2n = 34
Previous conservation statuses
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2022-2023 using the New Zealand Threat Classification System (NZTCS) – more information about this can be found on the NZTCS website. This report includes replaces all previous NZTCS lists for vascular plants. Previous assessments can be found here.
- Conservation status of vascular plants in Aotearoa New Zealand, 2023. 2024. Peter J. de Lange, Jane Gosden, Shannel P. Courtney, Alexander J. Fergus, John W. Barkla, Sarah M. Beadel, Paul D. Champion, Rowan Hindmarsh-Walls, Troy Makan and Pascale Michel Department of Conservation. Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2017 | Non-resident Native – Coloniser | Qualifiers: DP, SO
2012 | Non-resident Native – Coloniser | Qualifiers: SO
2009 | Non-resident Native – Coloniser | Qualifiers: SO
2004 | Non-resident Native – Coloniser
Referencing and citations
References and further reading
Sykes, W.R.; de Lange, P. J. 1993: Plectranthus parviflorus Willd. (Lamiaceae) in New Zealand. New Zealand Journal of Botany 31: 11-14.
Attribution
Fact Sheet prepared for NZPCN by P.J. de Lange 1 August 2003. Description modified from Sykes & de Lange (1993)
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Coleus australis Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/coleus-australis/ (Date website was queried)