Plant profiles > Clianthus
Family : Fabaceae
If one had to choose New Zealand's most spectacular flowering plant, the kakabeak (or kowhai-ngutu-kaka) would certainly be one of the leading candidates. In recent times, the large, bright red flowers that are borne by the two species of Clianthus have taken on additional poignancy, as emblems of the plight of New Zealand's threatened flora.
Clianthus puniceus clings to existence within nature, with the survival of just one plant on an island in the Kaipara Harbour, whilst Clianthus maximus is represented by less than 200 plants in the wild, after a spectacular decline within recent years. As with the now-popular Three Kings islands climber, Tecomanthe speciosa, cultivation beckons as being an essential tool in the conservation of both species of kakabeak.
Like many other members of the pea family, Fabaceae, kakabeak are associated with disturbed and marginal habitats, such as slipfaces or cliffs. They have also been historically associated with sites of pre-European Māori habitation, leading previously to the hypothesis that continual cultivation by Māori had ensured the survival of the species thus far. Though it is difficult to assert with any surety that the species would not have survived without deliberate cultivation, this has certainly played a role.
Although they grow vigorously within cultivation, Clianthus suffer from a range of threats within the wild and gardens. Snails (the scourge of many of our threatened species) can ravage plants, as do leaf-miners and other insects. Browsing animals are a serious threat within nature, as is drought.
Our experience of these species is that in many cases, they are best treated as comparatively short-lived ornamentals (3 to 4 years), that are regularly replenished. We continually experiment with growing them in different aspects, especially those that resemble the exposed shrubland habitats within which they occur in the wild (in order that we can cultivate more enduring stands of them). Our theory, whether it is correct or not, is that conditions that are challenging for plant growth are also challenging for the insects that affect these plants (and can act as a natural inhibiting factor). This certainly works in inhibiting attack by various organisms on other native species.
Although we are initially including an account of C. maximus within this plant profile (purely due to the fact that we have suitable images of that species), it is important to point out that it is critical (from a conservation perspective) that both species receive the attentions of gardeners and landscapers. C. maximus has become more fashionable within recent years, and as a result C. puniceus has declined in popularity. It should be remembered that both species are of equal cultural and botanical importance, and furthermore that the variations in flower colour (extending to pink and cream forms) that are present within the genus, are found within C. puniceus.
Kakabeak was discovered to Western science by Joseph Banks and Daniel Solander, at Tolaga Bay, on Captain Cook's first voyage to New Zealand in 1769.
Clianthus maximus
Kakabeak; kowhai-ngutu-kaka
The figure of William Colenso is both significant and controversial within New Zealand botany (and indeed he is a notable character within New Zealand's social history). This remarkable man was a missionary in 19th Century New Zealand, and a botanist of some note, who regularly corresponded with Joseph Dalton Hooker (then Director of Kew Gardens, and author of the first authoritative flora of New Zealand, 'Handbook of the New Zealand Flora').
Within taxonomy, various botanists are colloquially termed 'lumpers' or 'splitters', based on their willingness to acknowledge various forms of plants as being distinct species. Colenso's instincts were that of the latter, and he was sometimes considered overly keen to recognise new botanical entities1. The apparent differences between various forms of Clianthus led Colenso to assert two forms of the genus to be distinct2. However, this was not officially recognised at species rank, until Peter Heenan reappraised the genus in 2000.
So, in short, Colenso - who has at times been derided as too quick to proclaim taxa as being distinct - was right in this case.
Clianthus maximus now represents the majority of kakabeak left in the wild. It is found in eastern regions of the North Island, where it occupies successional habitats. The species name 'maximus' obviously refers to large size; not however, as one might expect, an appreciable size difference in the flowers, but rather within the leaves. In addition to being larger, the leaves of C. maximus are glossier. The colour of the flowers is considered to be a slightly darker red than C. puniceus.
C. maximus can reach up to 5m within nature, but dimensions of 2m are more usual within gardens. It has a vigorous, reaching growth form, and responds well to hard pruning.
Footnotes
- This is commonly known within botanical circles in New Zealand.
- The history of this is recounted in a very interesting article by one of my lecturers from my time at university, John Clemens, in the New Zealand Garden Journal (Vol. 5, No. 1, June 2002, pp. 4-5).