Synergizing Sustainability: Integrated Nutrient Management and Intercropping for Optimal Coconut Cultivation in South India

Abstract

The study highlights the importance of integrating organic resources, such as vermicompost and biofertilizers with inorganic fertilizers to sustain coconut yields and manage costs. The experimental trial was conducted from 2016 to 2020 in a 47-year-old East Coast Tall coconut garden at Coconut Research Station in South India. The research evaluated four nutrient management treatments viz., T1 (75% Recommended Dose of Fertilizer (RDF) + 25% N organic), T2 (50% RDF + 50% N organic), T3 (100% N organic) and a control (100% RDF). Intercrops included black pepper (Piper nigrum), banana (Musa acuminata) and cocoa (Theobroma cacao). Organic manure significantly improved soil physical properties, water retention and overall soil health. The T2 treatment achieved the highest yields for coconut, cocoa, banana and black pepper. The added soil health parameters supported to these findings, with T2 showing the highest fungal (15.27 × 103 cfu/g of soil) and bacterial populations (17.25 × 105 cfu/g of soil), along with a significant earthworm population (26/m2), indicating enhanced soil ecosystem health. Additionally, soil moisture content was highest under T3 (100% organic) across various depths, followed by T2, highlighting the critical role of organic matter in improving soil moisture conservation. The economic feasibility analysis, including a net present value (NPV), benefit/cost ratio (B/C ratio) and an internal rate of return (IRR), revealed T2 to be the most economically viable nutrient management strategy. This study highlights the economic benefits of intercropping coconuts using an integrated nutrient management (INM) approach, demonstrating its superiority over traditional monocropping practices.