Arum Lilies

Arum lily is a long-lived plant that is 1-1.5 m tall. It is known for its large, white flowers and recognisable leaves. New leaves grow from underground stems in autumn, followed by flowers in winter. Plants yellow off in areas with dry summers. In wet areas the plant is green year-round. 

Other varieties of arum lily are also invasive, including a green flowered version called ‘Green Goddess’.

Arum lily is an environmental weed throughout Western Australia, South Australia, Tasmania, New South Wales and south-east Queensland. Arum lily is common in coastal areas of New South Wales. It is most invasive on Lord Howe and Norfolk Islands.

Arum lily is also a weed in New Zealand.

Arum lily comes from South Africa. It was brought to Australia as a garden plant.

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Arum lilies may be visually spectacular, but for more than 100 years they have been wreaking havoc on the bush in the South West corner of Western Australia.

The South African plants have taken over huge swathes of the bush, choking out native flowers and killing livestock.

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HABITAT 

A weed of wetlands, swamps, waterways, gullies, irrigation ditches, neglected gardens, roadsides, open woodlands, waste areas, coastal environs and damp pastures in sub-tropical and warmer temperate regions.

HABIT 

A long-lived (i.e. perennial) clump-forming herbaceous plant with upright leaves and flowering stems usually growing about 1 m tall, but occasionally reaching up to 1.5 m in height. It produces creeping underground stems (i.e. rhizomes) and fleshy tubers.

Impact and control methods 

 

Arum lily (Zantedeschia aethiopica) is regarded as a significant environmental weed in Victoria and Western Australia, and as an environmental weed in South Australia, New South Wales and Tasmania. It is actively managed by community groups in Western Australia and was recently listed as a priority environmental weed in three Natural Resource Management regions. For more information from the NSW Government

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STEM AND LEAVES 

The leaves are all produced from the base of the plant, as are the smooth and fleshy (i.e. somewhat succulent) flowering stems. These flowering stems are up to 1.5 m tall, relatively thick and hairless (i.e. glabrous). The leathery leaf blades... Show more

FLOWERS AND FRUITS 

The 'flowers' (i.e. inflorescences) are large and very showy (up to 15 cm across). They consist of a large enclosing petal-like bract (i.e. a spathe), that is pure white or ivory-white in colour, which surrounds a central flower spike (i.e.... Show more

REPRODUCTION AND DISPERSAL 

This species reproduces by seeds and also vegetatively via creeping underground stems (i.e. rhizomes) and tubers. Seeds may be dispersed by water movement, birds and other animals. Local spread occurs via the creeping underground stems (i.e. rhizomes). These vegetative structures may... Show more

SIMILAR SPECIES 

This species is quite distinctive, however it may occasionally be confused with Italian arum (Arum italicum) and the native cunjevoi (Alocasia brisbanensis). These species can be distinguished by the following differences:

arum lily (Zantedeschia aethiopica) has green leaves and showy white inflorescences with a bright yellow flower spike in the centre. Its inconspicuous berries are yellowish-green to yellow in colour when ripe.

Italian arum (Arum italicum) has slightly variegated leaves and greenish-white inflorescences with a yellowish flower spike in the centre. Its orange or bright red berries are usually conspicuously displayed in elongated clusters when ripe.

cunjevoi (Alocasia brisbanensis) has green leaves and greenish coloured inflorescences with a greenish or yellowish coloured flower spike in the centre. Its bright red berries are usually conspicuously displayed in short, dense clusters when ripe. [3]