Calamus caesius

Cultivation Details

A plant of the more humid, lowland tropics, where it is found at elevations up to 800 metres. It grows best in areas where annual daytime temperatures are within the range 23 - 30°c, but can tolerate 16 - 34°c^[1]. It prefers a mean annual rainfall in the range 2,500 - 3,200mm, but tolerates 1,700 - 4,200mm^[1]. Succeeds with its roots in deep shade, whilst its stems climb up to the sunlight^[1]. Grows best on rich alluvial flats and other fertile land^[2]. Prefers a pH in the range 5.5 - 7, tolerating 5 - 8^[1]. Plants can grow on drier land, but growth is less vigorous^[2]. Prefers a position in the dappled shade of the forest, with its stems climbing up towards the light^[2]. Plants flourish under mild and seasonal flooding, but dislike severe floods^[2]. Overhead shade should be manipulated at about 6-monthly intervals for 2 - 3 years to ensure seedlings receive sufficient light to grow vigorously. About 50% light/shade conditions are ideal for rattan growth Given the correct balance of shade and light, plants grow away quickly from seed. After 12 - 14 months the primary stem may exceed 1 metre; the first climbing whips and 1 or 2 sucker shoots may have already developed^[2]. As the plant grows older, more and more suckers will be produced every year, probably up to ten per year. Some of these will develop into aerial stems while others remain dormant as bulbil-like shoots, thus forming a relatively compact cluster of aerial stems^[2]. By year 10, the number of aerial stems may vary from 20 to 60 or more per cluster, depending on conditions of growing site and weather^[2]. Aerial stems may grow at rates exceeding 4 - 5 metres per year^[2]. Annual flowering may commence at an age of 4 - 5 years. Up to 4 inflorescences may be produced on one flowering stem, with each infructescence bearing 1,000 - 1,500 fruits^[2]. Selective harvesting of mature canes can be carried out from the eighth year after planting^[2]. Harvesting is carried out by cutting the rattan cane at about 30cm from the base, pulling the cane down out of the canopy as much as possible, removing the leaf-sheaths by twisting the cane around a tree trunk or hitting it with a knife. The cane, divested of its sheaths, is then cut into lengths of about 6 metres and bent, and tied in bundles of 100 pieces. Inevitably, lengths of canes will be left in the canopy and cannot be pulled out because they are entangled with the tree branches. More efficient mechanical methods of harvesting for large commercial plantation have yet to be developed. Canes should be processed soon after harvesting, in order to maintain their quality^[2]. Highly variable yield figures, ranging from 1.5 - 3 tonnes/ha per year, have been provided by cultivators and researchers. Based on a surviving population of 500 plants/ha in a commercial plantation, a cane growth rate of 2.5 metres/year and 36 000 metres of dry canes to yield one ton, the yield has been estimated to increase from 0.5 tonnes/ha per year in year 9 from planting to 1.5 tonnes/ha per year in year 12 and thereafter^[2]. This species is closely related to C. Optimus and C. Trachycoleusc. Whereas this species and C. Optimus produce short horizontal stolons not exceeding about 8 cm, C. Trachycoleus produces long horizontal stolons up to 1 metre or more long. As a result, this species produces a relatively compact cluster of aerial stems whereas .C. Trachycoleus has a diffuse colony of aerial stems which are more widely spaced and hence compete less with each other. The diffuse colony of C. Trachycoleus makes it an aggressive colonizer and a potentially higher cane yielder^[2]. A dioecious species, both male and female forms need to be grown if fruit and seed are required.