Title : Integrating vermicomposting into circular agricultural systems: opportunities, challenges, and lessons from 20 years of research
Abstract:
As global agriculture faces mounting pressure to reduce environmental impacts while maintaining productivity, circular economy approaches offer promising pathways toward sustainability. Vermicomposting technology represents a critical intervention in closing nutrient loops, transforming diverse organic waste streams into valuable agricultural inputs, and reducing dependency on unsustainable resources such as peat. This presentation synthesizes two decades of research and practical implementation experience in developing and scaling vermicomposting systems for sustainable agriculture across diverse contexts in Norway and Ethiopia. The work examines both the opportunities and challenges encountered in integrating vermicomposting into circular agricultural systems, including applications in growing media formulation, organic fertilizer production, and plant protection. The research integrates multiple approaches including controlled experimental studies, on-farm trials, and commercial-scale implementation of vermicompost production systems. Key research areas include: (1) comparative studies of vermicomposting processes using different mixes of bio wastes, evaluating the quality of resulting vermicomposts and liquid organic fertilizers extracted from diverse feedstock combinations; (2) peat substitution in growing media using vermicompost derived from food waste digestate and green waste compost, demonstrating successful reduction of peat content down to 25% while maintaining plant performance; (3) development of stable liquid organic fertilizers (Edel Juice) from various vermicompost sources for both soilbased and hydroponic systems; (4) biochar-enhanced vermicompost formulations as sustainable alternatives to peat-based growing media; and (5) integrated waste management systems combining vermicomposting with advanced technologies. Research demonstrates that feedstock composition significantly influences vermicompost quality and extraction efficiency of liquid fertilizers, with different bio waste combinations yielding vermicomposts with distinct nutritional profiles and biological properties. Vermicompost successfully substitutes up to 75% of peat in potting media without compromising germination, plant growth, or root development in vegetables such as lettuce and head cabbage. Vermicompost-derived liquid fertilizers achieve comparable or superior performance to conventional chemical fertilizers while maintaining stability for over six months. Studies reveal that vermicompost enhances plant nutrition through higher availability of nitrates, phosphates, and exchangeable nutrients, while providing biological benefits including disease suppression and improved plant resilience. However, challenges persist in managing high pH levels, optimizing physical properties of compost-based media, ensuring consistent product quality across different feed stocks, and achieving economic viability at commercial scale. Successful integration of vermicomposting into circular agricultural systems requires understanding how different bio waste inputs affect product quality and application potential. The technology proves particularly valuable for processing diverse organic waste streams including food waste digestate from anaerobic digestion facilities, converting low-quality materials into high-value agricultural products tailored to specific applications. Future development must focus on feedstock standardization, quality assurance protocols, optimization of processing parameters for different waste combinations, and creating enabling policy frameworks to support broader adoption of these technologies in professional horticulture and sustainable farming systems.
Keywords: Vermicomposting, Circular Agriculture, Organic Waste Management, Biowaste Valorization, Peat Substitution, Growing Media, Liquid Organic Fertilizers, Sustainable Farming
