EVALUATING HUMIC ACID CONTENT IN THE PROCESS OF COMPOSTING COFFEE HUSKS USING E.M PRODUCT AND SUPPLYING THESE FOR COFFEE TREES (Coffea robusta)

Abstract

Coffee husk has a high content of organic substance, which is very suitable for organic fertilizer production. However, current composting process often takes time, leading to leak mineral substances in organic fertilizer. Being composted with E.M, the humic acid content of these coffee husks is 12.45% in dry weight, and the husks can be used for crop plants after 6 weeks of composting. An experiment was conducted using organic fertilizer for coffee trees. The result showed that the coffee bean productivity was not significantly different from using inorganic fertilizer or organic fertilizer composted by Trichoderma product. The ratio of the forming fruits after 6 months of fertilization showed that the amount of coffee fruit bunch per branch was 17.1, which was higher than the coffee trees used inorganic fertilizer or organic fertilizer in the control treatment, were 14.9 and 15.8, respectively.