COCONUT HUSK ASH AS A FERTILIZER FOR COCONUT PALMS ON PEAT

SUMMARY We demonstrated experimentally that coconut husk ash is an excellent mineral fertilizer for immature coconut hybrids on developed peat, providing potassium (K) in particular. Coconut husk ash performed as well as potassium chloride (KCl) in a proportion of 2–2.5 to 1. At four years, 99% of coconut palms fertilized with husk ash, 92% of coconut palms fertilized with KCl and 26% of control palms were sexually differentiated. The cumulative yield in the first two harvesting years more than trebled between control palms (26 nuts per tree) and the palms fertilized with KCl (93 nuts per tree) or husk ash (105 nuts per tree). This is an important result, given the intensity of K deficiency and the increasing cost of imported fertilizers. Although coconut husk ash will never totally replace K fertilizer, it can recycle a substantial proportion of nutrients in a coconut plantation. It now remains to optimize its use on an estate level, by examining the feasibility and cost-effectiveness of its mass production and determining conditions for maximum efficiency.