24/08/2026
The Salak Challenge Part 1 Introduction
Introduction
There are 20 species of salak palms, all endemic to south-east Asia. Some species have long been favoured as a desired food. The most popular varieties are grown in Bali, particularly around the village of Sibetan, which lies a close distance from the volcano, Mount Agung. In 1993 there were 12 million salak palms consisting of 13 cultivars growing commercially, producing about 32,000 tons of fruit. This demonstrates how highly valued this fruit is to Indonesians.
The salak palms in this region are cultivated on deep volcanic ash beneath a forest canopy. The palms optimally grow in an environment at temperatures between 22C to 32C, high humidity, 1700mm to 3100mm of rain per annum with only a short dry season. The palms are intolerant to full sunshine - about 50 – 70% shade is required.
These palms are slender stemmed with adventitious roots. Their fronds can reach 6m in length and are covered in many sharp, large, woody thorns creating a very hazardous working environment. As the palms age, they are made to “lay” down. Fifty-year old palms can be seen rooted in their current location and their old stems can be traced back some 3m distance to where they were first planted.
Grown under the optimal conditions, the palms are capable of producing 3 crops per year, but the main crop falls around summer/autumn. The fruit are produced in clusters of 10-20 fruit, each about the size of a golf ball. It is uncertain how long a palm can remain productive, but it is greater than 50 years.
Each of the cultivars vary slightly in their eating qualities. They mostly have a mild, sweet flavour with a slight astringent after taste. The exception is - Salacca zallaca (Bali) sub. Amboinensis var. “gula pasir” meaning “sand sugar” which, as the name suggest, is sweet with no astringency, making it the most expensive salak fruit to purchase. As if that wasn’t enough, this is the only variety that is bisexual – it will self-pollinate. All other species/varieties have separate male and female plants.
The Challenge
In 2015 I was gifted a few Gula Pasir seeds. The first 2 that I planted out died from sun over-exposure. The next 2 were planted beneath mature trees providing about 80% shade. The next problem to resolve was that the planting site was relic beach sand dune situated 2m from the edge of an estuarine mud flat. This substate is impoverished compared to the rich volcanic ash of its native lands. Over the years I constantly applied mulch, compost, coffee grinds and chicken manure, watering weekly during the dry seasons, but growth was very slow.
In 2018, I travel to Sibetan Village to observe how they were grown.
During the summer of 2025 one tree produced 2 flower spikes that failed to fruit. It occurred to me to try something a little different – I placed 6 X 20 litre buckets of volcanic scoria around the base of each tree and applied a dose of micro-elements. In August 2026, one spike appears to be developing fruitlets. This without a doubt self-pollinated as the second palm has not yet produced a flower spike and there would not be another salak palm within a 20km distance.
To be continued.
Photo: a) mature Gula Pasir fruit clusters on farm at Sibetan Village b) the first tiny, developing fruits at Trinity Park
