Species

Hibiscus diversifolius subsp. diversifolius

Etymology

Hibiscus: Name of very ancient origin used by the Roman poet Virgil for the marsh mallow plant.
diversifolius: with differing or varied leaves; from the Latin diversus and folium; leaf shapes

Common Name(s)

Native hibiscus, swamp hibiscus, prickly hibiscus

Current Conservation Status

2012 - Threatened - Nationally Critical

Conservation status of New Zealand indigenous vascular plants, 2012
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2012 using the New Zealand Threat Classification System (NZTCS). This report includes a statistical summary and brief notes on changes since 2009 and replaces all previous NZTCS lists for vascular plants. Authors: Peter J. de Lange, Jeremy R. Rolfe, Paul D. Champion, Shannel P. Courtney, Peter B. Heenan, John W. Barkla, Ewen K. Cameron, David A. Norton and Rodney A. Hitchmough. File size: 792KB

Previous Conservation Status

2009 - Threatened - Nationally Endangered
2004 - Threatened - Nationally Vulnerable

Qualifiers

2012 - DP, RR, SO, Sp
2009 - SO, Sp

Authority

Hibiscus diversifolius Jacq. subsp. diversifolius

Family

Malvaceae

Brief Description

Sprawling tangled thorny shrub bearing broad thin leaves and large dark-centred flowers forming dense thickets by streamsides and in wetlands in northern Northland. Stems with small hooks. Leaves to 100mm long and 80mm wide, with 3-5 uneven irregular teeth, on long thorny stalk. Fruit a dry hairy 20mm long capsule.

Flora Category

Vascular - Native

Structural Class

Dicotyledonous Trees & Shrubs

Synonyms

The only synonym applicable to New Zealand is Hibiscus taylorii Buchanan nom. nud.

Distribution

Indigenous. In New Zealand this species has apparently always been restricted to the northern most extremity of the North Island (from about Reef Point and Doubtless Bay north). The largest populations known occur on the eastern side of Te Paki. However, several of these owe to their origins to deliberate plantings by conservation minded locals. Outside New Zealand this species is also known from tropical Africa, Australia, New Guinea, the Philippines, many Pacific Islands and Central and South America. New Zealand plants match subsp. diversifolius.

Habitat

Coastal wetlands and streamsides. Often growing amongst raupo (Typha orientalis C.B.Presl) at the back of dune slacks or close to brackish streams. Very rarely in gumland scrub or on ultramafic rubble.

Features

Semi-erect, erect or prostrate, widely spreading, much branched subshrub or shrub typically forming dense intertangled thickets up to 2 × 3 m, or creeping masses. Stems stout and woody, especially near base. Young branches and leaf petioles copiously clad in numerous small, sharp, 1–2 mm conical prickles and dense, fine stellate hairs. Petioles up to 80 mm long. Leaves 50–100 × 30–80 mm, lamina ovate, orbicular to suborbicular, shallowly to deeply palmately 3–5-lobed, broadly to shallowly cordate or truncate, margins irregularly crenate–dentate to dentate–serrate, upper surface sparsely hispid hairy, undersides often densely so. Inflorescences in 5–20-flowered (sometimes more) terminal apparent racemes. Flowers 50–80 mm diameter; pedicels 1–3 mm long, prickly. Epicalyx segments 7–12, narrowly lanceolate, 8–12 mm long, shortly connate at base, hispid. Calyx 7–12 mm long, densely clad in hispid or stiff straight hyaline hairs, lobes narrowly deltoid to lanceolate, c. 10 mm long. Petals 35–40 × 50–58 mm, obovate, pale lemon–yellow, with a dark maroon base. Capsule 20 × 20 mm, ovoid, clad in long stiff hairs. Seeds 3.6–5.0 mm long, reniform to irregularly triangular, pale to dark brown or black-brown, sometimes with paler stripes, surface glabrous, smooth or irregular.

Similar Taxa

A well marked species easily distinguished from other Hibiscus species cultivated or naturalised in New Zealand by the prickly stems and leaf petioles.

Flowering

September - April (but sporadic flowering may occur at anytime of the year)

Flower Colours

White,Yellow

Fruiting

October to May (but fruit may be found at anytime of the year)

Propagation Technique

Very easily grown from fresh seed and semi-hardwood cuttings. An attractive shrub, ideal for a coastal garden or sheltered situation when grown inland. Rather frost tender, in cooler areas it can be treated as a vine and grown up walls which protects it from frost. The prickly stems and petioles can be unpleasant. The creeping form reputedly from the Surville Cliffs makes an ideal ground cover. Hibiscus diversifolius can be grown around ponds and in boggy ground.

Threats

This species is under severe threat from the actions of browsing animals, particularly wild cattle and horses which greedily devour it wherever they can find accessible plants. Some populations at Tokerau Beach have been eliminated by coastal housing development.

Chromosome No.

2n = 72

Endemic Taxon

No

Endemic Genus

No

Endemic Family

No

Where To Buy

Periodically offered by most commercial garden centres. Plants are held by several specialist native plant nurseries. Two forms seem to be available, an erect shrub-forming plant typical of the wild New Zealand form, and another prostrate, creeping form, said to have come from the ultramafic rocks of the Surville Cliffs, North Cape. Can be purchased from oratia Native Plant Nurseries (info@oratianatives.co.nz).

   

Attribution

Fact Sheet Prepared by P.J. de Lange (1 November 2009). Description by P.J. de Lange subsequently published in de Lange et al (2010).

References and further reading

de Lange, P.J.; Heenan, P.B.; Norton, D.A.; Rolfe, J.R.; Sawyer, J.W.D. 2010: Threatened Plants of New Zealand. Canterbury University Press, Christchurch.

Johnson, A. T. and Smith, H. A (1986). Plant Names Simplified: Their pronunciation, derivation and meaning. Landsman Bookshop Ltd: Buckenhill, UK.

This page last updated on 7 May 2014