UTILISATION OF COCOA POD HUSK FOR THE PRODUCTION OF ORGANIC FERTILIZER AS A WASTE MANAGEMENT STRATEGY

Abstract

Cocoa pod husks (CPU) disposal constitutes a serious problem in cocoa farms and cocoa processing areas. In its raw or processed form, CPH has the potential to be used as organic fertilizer but few studies have been conducted in Nigeria. This study was designed to determine the perceptions and practices of cocoa farmers regarding the disposal of CPH as well as its utilization of CPH as organic fertilizer to raise cocoa seedlings in nurseries. In the experimental component, composite was made using CPH only and 1:1 v/v of CPH and Goat dung (GD) to mixture by weight. Raw CPU was allowed to decompose naturally. Exhausted soil devoid of any amendment was used as control. The three composite were monitored for 54 days and were used for cocoa seedling production using 25, 50, 100 and 200 kg ha⁻¹ application rates with four replicates each for 10 weeks. A stratified random sampling using proportional allocation based on the number of cocoa farmers in the 36 farm settlements in Ado-Ekiti was done to select 400 cocoa farmers that were interviewed with the aid of a questionnaire. Descriptive statistics were used to analyse the data generated. The composted CPH only, showed that it contained 4.9% Nitrogen, 0.6% Phosphorous, 3.6% Potassium, 33.3% Carbon and 17.0% moisture while the uncomposted CPH contained 2.7% Nitrogen, 0.1% Phosphorous, 3.0% Potassium, 31.8% Carbon and 11.7% ash content indicating that cornposting enhanced Nitrogen, Phosphorous, Potassium and Carbon contents. However, composted CPH+GD (1:1 v/v) contained 5.9% Nitrogen, 0.5% Phosphorous, 4.1% Potassium and 22.0% moisture. Composting thus improve Carbon, Nitrogen, Potassium and moisture contents as compared to composted CPH only and uncomposted CPH (control). The effects of composted CPH+GD (1:1 v/v), composted CPH only and uncomposted CPU on the plant height (16.1cm, 7.5cm and 9.5cm), stem girth (2.6cm, 1.6cm and 1.4cm) and number of leaves (10.5, 5.9 and 5.6) of the planted cocoa seedlings at the tenth week after planting showed that composted CPH+GD (1:1 v/v) medium was highest and significantly different (P<0.05) from those grown on composted CPH only and uncomposted CPH. Application rate of 200 kg ha⁻¹ supported the highest plant height (15.5cm), stem girth (3.1cm) and numb of leaves (11.0) of coma seedlings than the lower rates, which were not significantly different from themselves. All the participants submitted to leaving CPH in heaps after extracting the cocoa beans. About 93.0% believed that this practice could promote black pod disease while others (7.0%) believed that the heaps only occupy space in their plantations. Participants reportedly used CPH for soap making (38.3%) and medicinal purposes (61.8%). The performance of the seedlings raised on composted CPH +GD (1.1 v/v) suggests its potential as a good organic fertizer for cocoa nurser. However, farmers have limited knowledge about its use as a fertilizer.