New Zealand jasmine: a real endemic climber!

For the latest instalment in our horticulture series we’re focusing on a sweet-smelling climbing vine Parsonsia heterophylla, also known as New Zealand Jasmine, akakiore and kaihua.

Parsonsia are part of the Apocynaceae or dogbane family of flowering plants which include introduced species most home gardeners would be familiar with – such as milkweed and periwinkle.

The genus was named after James Parsons, an 18th century botanist and natural historian, which contains upwards of 40 plant species found across tropical Asia, Australia and New Zealand.  The species name heterophylla means ‘varied leaves’ – apt for a plant with such diverse leaf colours and structures; from broad and short, to thin sword-shaped leaf forms that can all occur in a single specimen.

New Zealand has three endemic Parsonsia: the most common is Parsonsia heterophylla this cream-flowered variety which is naturally found in wet lowland forests from Manawatāwhi (Three Kings Island) to Rakiura (Stewart Island); Parsonsia capsularis found north of Auckland with shades of yellow, red or pink flowers and rarer still Parsonsia praeruptis which is confined to a 120ha area of ultramafic rocks known as the Surville Cliffs Formation at North Cape. It flourishes prolifically there, yet as it is of interest to browsing possums, it has a threat status of 'Threatened / Nationally Endangered'.

Parsonsia heterophylla is the largest of all three species (with the largest leaves and flowers) that displays profuse clusters of small creamy-white flowers from spring until autumn each year, that will eventually form fruit. These fruit take the form of long thin pod-like capsules that release numerous tufted seeds with long silken hairs into the wild, to be blown about and dispersed.

This fast-growing evergreen can grow up to ten metres tall with reddish brown branches that twine around other trees, shrubs or other suitable supports such as trellis or railings.

Although not of great traditional use by Maori, Parsonsia flowers were occasionally used for hunting - fastened to the perches of bird-traps as a lure, with the vines used for tying up boundaries and fences.

The endemic moth Stigmella kaimanua from the Nepticulidae family has a mutualistic relationship with kaihua where larvae will tunnel into or mine the leaves of this plant and live safely while consuming the leaf tissue for food.

A beautifully scented plant for the home garden, kaihua grows well in most conditions. It is easy to propagate with seeds or with cuttings.  You can see and smell the gorgeous flowers of kaihua twining along the railing in our Wetlands aviary, in Te Wao Nui. 

Stay tuned for the next blog in this series and if you have any recommendations on plants we should cover or questions for our horticulture experts, flick us an email!