Salacca wallichiana

Cultivation Details

Salacca wallichiana is a plant of the hot, moist tropical lowlands^[1]. It grows in areas where the mean annual rainfall is within the range 2,500 - 3,000mm with a dry season of 5 - 6 months^[1]. A dry season is needed for good fruit set; spadices emerging in the rainy season tend to rot and the viability of the pollen is poor^[1]. The temperature range required is 22 - 32°c; lower temperatures reduce flowering^[1]. Thrives in soils ranging from sandy loam to heavy clay^[1]. On low-lying wetlands it grows better than most fruit trees^[1]. Prefers a pH in the range 5 - 6, tolerating 4.5 - 6.5^[2]. Established plants can stand drought very well but, for a good yield of fruit, irrigation is required in the dry season^[1]. In its natural habitat and in mixed orchards rakum is commonly found growing under shade, but in commercial orchards the palms can be grown successfully without shade, provided they are irrigated^[1]. Plants commence flowering when about 5 - 6 years old^[1]. The plant flowers all year round, the fruit ripening 7 - 9 months after flowering^[1]. Nearly all fruit set, however, takes place early in the dry season, leading to a very seasonal harvesting of the fruit^[1]. The average annual fruit yield varies between 6 - 12 t/ha depending on the cultivars. The skin of 10 - 16 week-old fruitlets is brown, turning darker to almost black at 17 - 23 weeks, gradually changing to orange when the fruit ripens^[1]. The flesh of 10 - 19 week-old fruits is off-white and turns to light yellow when the fruits are 20 - 22 weeks old; as the fruit grows it gradually assumes a more yellow-orange colour^[1]. The stones in 10 - 19 week-old fruits are white and contain a jelly-like substance. The colour changes to yellow at 20 - 23 weeks of age and to brown thereafter while the contents harden^[1]. For the superior sala cultivars, harvesting time is 36 weeks and not later than 38 weeks after pollination^[1]. At harvest each fruit cluster or the entire infructescence is cut with a hooked knife or pruning shears on long handles^[1]. In young non-bearing orchards, removing suckers is the most unpleasant chore, but a must. One or two stems per clump are sufficient for good yield^[1]. Dense clumps yield poorly and are difficult to harvest^[1]. Leaf pruning is not advisable, but may be necessary to facilitate orchard operations^[1]. Hand pollination can raise yields substantially^[1]. Several cultivars with superior fruits have been developed^[1]. A dioecious species, both male and female forms need to be grown if fruit and seeds are required^[1]. About 1 male plant to every 15 females is considered sufficient for good pollination^[1]. Xenia effects are quite noticeable in S. Wallichiana, so it is important to choose a compatible male strain^[1].