HORTICULTURAL WASTE MANAGEMENT AND COMPOSTING FOR ENVIRONMENTAL SUSTAINABILITY

Purpose: This paper examines the generation, management, and composting of horticultural waste in Jos Metropolis, Nigeria, to evaluate its potential for advancing environmental sustainability. Specifically, the study quantifies waste composition, assesses the agronomic impact of compost on soil fertility and vegetable yield, and identifies barriers limiting the adoption of sustainable waste practices among horticultural stakeholders.

Design/methodology/approach: A mixed-methods empirical approach was employed, integrating surveys, waste audits, and experimental field trials. Data were obtained from 150 participants comprising gardeners, estate managers, and municipal workers. Thirty paired horticultural plots were monitored to compare pre- and post-compost soil properties and yield performance. Quantitative data were analysed using descriptive statistics and paired t-tests to determine significant changes in soil and crop parameters following compost application.

Findings: Results show that approximately 67% of horticultural waste in Jos is biodegradable and suitable for composting, yet 56% of respondents still resort to dumping or burning. Composting significantly increased soil organic matter (from 1.8% to 3.6%), total nitrogen (0.09% to 0.16%), available phosphorus (6.2 to 14.8 mg/kg), and vegetable yield (by 22%), while reducing bulk density (1.45 to 1.28 g/cm³). Barriers to adoption included limited technical knowledge, inadequate funding, lack of space, and poor institutional support.

Research limitations/implications: The study was limited to one urban area and a single cropping season. Broader, multi-location research would strengthen external validity and enable comparative policy insights for urban waste management across Nigeria.

Practical implications: The study recommends integrating composting into municipal waste systems, establishing community compost hubs, enforcing compost quality standards, and supporting small-scale producers through training and micro-finance schemes.

Originality/value: This paper offers one of the first empirical assessments linking horticultural waste management with measurable soil and productivity outcomes in a Nigerian urban context. It provides a replicable evidence base for policymakers and practitioners seeking sustainable waste-to-resource solutions in sub-Saharan African cities.