A Gift from Borneo

A small bush from Borneo called Sweet Leaf provides a steady source of ‘spinach’ to people living in the tropics.

WORDS BY DAVID CHANDLEE, PHOTOGRAPH BY DIGBY GOTTS 

First published in the Cardwell/Johnstone Branch RFCA Newsletter No.20, August 1990 and then republished in the RFCA Newsletter No.65 6/90

Soon after first arriving as a visitor to Sabah in Borneo I noticed a small upright shrub with purple flowers and fruits growing in gardens. It had alternate arranged, 40-60 mm long elliptic dark green leaves, sometimes with a silver blaze, and a drip-tip. Lauren and I were to see this plant in every garden in every back (or front) yard in Sabah and Sarawak. Later we found out it is also commonly grown in Peninsular Malaysia, Sumatra and Java as well. The plant is “Sweet Leaf Bush” – Changkok manis or Sayor manis in Malay, Sauropus androgynous L. Merr.). Soon we were eating it in soups with seasonings and as an accompaniment to rice dishes. We found it sweet and good flavoured, with a good texture when cooked.

We sent seeds back to North Queensland and began distributing the plants in 1985. Five years later it is growing from Rockhampton on the Tropic of Capricorn to Cape York Peninsula near the Equator, and is used by its growers as a steady source of “spinach” during the warm and hot months of the year, when green leaves become a luxury imported from southern Australia. One enthusiast is planting an acre in Sweet Leaf!

Ease of cultivation, rapid growth, and good taste as well as its high rate of production and high crude protein levels (varying from 6-9%) are the main features which attract growers to the Sweet Leaf Bush. Gardeners who seek a healthy diet rich in non-meat protein, minerals, vitamins and fibre will find that if they regularly prune their plants they can have a constant supply of tasty “spinach” of good quality.

Any available soil will do for Sweet Leaf Bush, be it clay, loam or sandy. As long as it is warm it will tolerate heavy rain or hot sun, as well as the 95% shade it endures in its native habitat, the understorey in primary rainforest. Fertiliser is not necessary but it does respond favourably if mulched. The purplish fruits are edible, as are the flowers, and some people appreciate the younger leaves raw, though it is more commonly cooked.

In the garden Sweet Leaf also is useful as a shade plant to grow other more tender vegetables underneath, thereby keeping off the hot sun. It is propagated by seed or cuttings, and can be harvested four months after planting.

Uses: As well as being a good ingredient in stir fried dishes, it is also good in scrambled eggs, and any dish which calls for parsley or spinach.

Note: Although the author has yet to hear of it in Australia, in Malaysia there are occasional reports of headaches caused in some people by heavy consumption of Sweet Leaf. 

Below is a table detailing plant analysis. Analysis of some other foods is given for comparison.

TABLE 1
Analysis of Sweet Leaf Bush Sauropus androgynous

Moisture content 70%
Crude protein 35% (on dry matter basis)
Potassium 2.77% (Dried bananas 1.48%)
Calcium 1% (Dried skim milk 1.3%)
Phosphorus 0.61% (Dried soybeans 0.55%)
Magnesium 0.55%
Iron 199 ppm (Dried parsley 410 ppm)
Vitamin A High
Vitamin B Moderate
Fibre 14-18%