Here, a sensor-based machine learning approach has been presented to predict the maturity and monitor gas emissions during the composting process. By analyzing key environmental factors and emission data, our study aims to enhance the ecological responsibility of composting as a waste management solution. Our research combines a dedicated sensor system with machine learning. The sensor system, integrated with Arduino Mega 2560 R3 and ESP-32 microcontrollers, wirelessly transmits data for remote monitoring. Meanwhile, our machine learning framework analyzes features such as temperature, C/N ratio, ammonia concentration, pH levels, and nitrate content from ten datasets. After rigorous preprocessing and model training with a robust five-fold cross-validation, we optimize hyperparameters using GridSearchCV. The results highlight that both XGBOOST and CatBOOST excelled in achieving the highest predictive accuracy among the models, each attaining an impressive R2 of 0.9912. In particular, XGBOOST demonstrated the lowest mean absolute error (MAE) at 1.1845, while CatBOOST exhibited the lowest mean squared error (MSE) at 1.8382. The interpretability of the model is ensured through LIME and SHAP, making complex models transparent and understandable. The results indicate that the XGBOOST model outperforms the others, achieving the highest predictive accuracy. This groundbreaking approach bridges scientific rigor with practical usability, ensuring responsible waste management for a sustainable future. Real-world applications of our research include more efficient and environmentally friendly waste management systems, reduced environmental impact, and improved compost quality for agricultural use.