Greenhouse gas emission of coffee seedling production: Comparative analysis of generative, vegetative, and grafting methods

The second-largest coffee producer globally, Indonesia, is overwhelmingly dependent upon farmers with small estates (smallholders), meaning the sustainability and climate adaptability of coffee seedling production has long-term implications for supply. Advancing nursery practices through footprint-friendly propagation is key to lowering greenhouse gas (GHG) emissions while maintaining seedling quality and performance. This study aims to assess the environmental performance and climate-resilience potential of coffee seedling production across three propagation methods: Generative Seedlings (GS), Vegetative Seedlings (VS), and Grafting Seedlings (GfS). A Life Cycle Assessment (LCA) was conducted in accordance with ISO 14040/44, using the ReCiPe 2016 impact assessment method. The functional unit (FU) was defined as one ready-to-plant coffee seedling. The system boundary extended from pre-nursery to nursery, encompassing land preparation, seed or cutting preparation, grafting operations, and transplanting. Organic fertilizer application, fuel transportation, and the use of plastic polybags were also included. Environmental impacts were assessed most comprehensively through Global Warming Potential (GWP, kg CO 2 -eq/FU) and additional midpoint indicators. The results indicate widespread differences among the propagation techniques. GfS had the highest GWP at 0.017 kg CO 2 -eq/FU, mainly due to increased nursery activities, inoculation during transplantation, a longer growth cycle, and higher resource inputs such as materials and energy. GS showed a moderate impact at 0.011 kg CO 2 -eq/FU, primarily driven by seed treatment and fertilizing agents. The vegetative scenario (VS) exhibited the lowest environmental impact at 0.0018 kg CO 2 -eq/FU, highlighting its greater potential for reducing climate impacts and resource consumption. Contribution analysis revealed that fuel transportation, water use, organic fertilizer application, and plastic polybags were the main contributors to environmental hotspots in soilless systems across all scenarios. The study finds that vegetative propagation probably has the lowest environmental impact when reducing GHG in sprouted coffee seedlings. Although grafting has higher environmental costs, its benefits in climate resilience and disease resistance present a trade-off between ecological impact and adaptability. Sustainable development can be advanced by boosting input efficiency, reducing fossil fuel transport, and switching from plastic polybags to biodegradable alternatives. These insights offer a quantitative foundation for implementing low-carbon practices in climate-smart coffee nurseries.