Weed Watch – Ice plant

 

 

Carpobrotus chilensis - one of the hybrids easily identified by its deep magenta flowers.

Carpobrotus chilensis – one of the hybrids easily identified by its deep magenta flowers.

Carpobrotus edulis and its hybrids are classed as Unwanted Organisms in New Zealand and are listed on the National Pest Plant Accord.

 

This native to South Africa is known my a host of names – Hottentot-fig, sour fig, Cape fig and many more – but in New Zealand it is most commonly called ice plant and here,  it has a long history as a pretty ornamental garden plant.

 

It thrives in many sub-tropical regions throughout the world and in a number of those, it has escaped cultivation and become invasive, creating a serious ecological problem by forming vast, mono-specific zones, lowering biodiversity and competing directly with several threatened or endangered plants for nutrients, water, light and space.

 

In New Zealand, the species has become naturalised in coastal areas, sandy pastures, along cliff tops, sand dunes and roadside cuttings, and it frequently displaces other vegetation. It can also change the structure of sand dunes. The South African ice plant species (Carpobrotus edulis), hybridises with and replaces the much smaller, pale pink-flowered native ice plant (Disphyma australe).

 

Carpobrotus edulis - an 'Unwanted Organism.'

Carpobrotus edulis – an ‘Unwanted Organism.’

Carpobrotus edulis  is a creeping, mat-forming succulent species and a member of the stone plant family (Aizoaceae), one of about 30 species in the Carpobrotus genus.  C.edulis  is easily confused with its close relatives, with which it hybridises easily, although it can be distinguished by the colour of its flowers – large, yellow or light pink blooms. Carpobrotus chilensis has smaller, deep magenta flowers.

 

The ice plant is long-lived and is a common sight around some parts of Te Waihora, particularly along Kaitorete Spit and the beach areas just south of the spit. The species reproduces by seed and also vegetatively via its fleshy stems.

 

The fruit of Carpobrotus edulis are edible when fresh and reportedly have a strong, astringent, salty, sour taste.  The leaf juice is astringent and mildly antiseptic and has been used as an old remedy for everything from sore throats and skin rashes to constipation and tuberculosis.