Piper sarmentosum

wild betel leaf


Piper sarmentosum

Roxb. 1812

pronounced: PY-puh sar-men-TOH-sum

(Piperaceae — the pepper family)


common names: wild betel leaf, Vietnamese pepper

Piper is the Latin name for pepper; sarmentosum is from the Latin sarmentum, a twig or branch, and sarmentosus, full of twigs – botanically the word is used as ‘producing runners’.

This spreading vine from south-east Asia has only fairly recently been found growing in Australia. Specimens in the National Herbarium come from Christmas Island in 1976, and Thursday Island, where it was reported as ‘cultivated’ in 2002. It has now appeared in Nelly Bay, no doubt as a garden escapee. The popularity of Thai cuisine is surely responsible for its appearance. The Christmas Island patch, found at Drumsite, was reported as ‘spreading and now covering a substantial area’. On Thursday Island, it was reported as ‘common’ with stock reportedly obtained from a Thai woman. The Nelly Bay patch has been poisoned, but I understand not completely eradicated.

Piper sarmentosum is an erect herb up to about 80 cm high, glabrous, and with long creeping procumbent branches. The stems are rounded, swollen at the nodes. The leaves are simple, cordate and alternate, 7 – 15 cm long by 5 – 10 cm wide. They are dark green, very glossy, with the petiole 2.5 – 5 cm in length.

The inflorescence is an axillary cylindrical spike, with some bisexual and some unisexual flowers each about 7 mm long. The bracts are more-or-less circular, white, with short stamens and 3 or 4 stigmas. The fruit is a mulberry-like berry with a sweet taste when ripe, rather like the taste of Elaeocarpus serratus, the Ceylon olive.

Piper sarmentosum (wild betel leaf, daun kaduk) is very similar in appearance to Piper betle (belel leaf, daun sireh), and the two are often confused. The latter is the leaf chewed with the areca nut and calcium hydroxide as a stimulant. The former is used as an ingredient in local cooking in many parts of south-east Asia. Probably the best known of the dishes featuring it is otak-otak. This is a fish cake with many regional variations. The Penang version is made from a mixture of eggs, fish fillet and a whole lot of herbs including lemon grass, galangal, ginger, fresh turmeric, dried chillies, morinda, kaffir lime leaf on a bed of wild betel leaf, and the whole thing wrapped with banana leaf. It is all held together by a coconut leaf rib, or, nowadays, simply stapled.

Wild betel leaf is also an ingredient in perut ikan, a pickled fish stomach curry, and nasi ulam, a herbed rice salad. It lacks the slightly minty taste of the Piper betle leaf.

The plant is easy to grow, and spreads by putting out roots at the nodes. It is fond of damp, shady places, and is often found growing near drains.


Photographs taken in Nelly Bay 2012, Picnic Bay 2016
Page last updated 13th March 2019