This study investigates the role of black plastic mulch (BPM) in regulating soil temperature and enhancing tomato yield in the Garhwal Himalayas, a region characterized by diverse climatic conditions and challenging agricultural practices. The use of BPM is explored as a strategy to optimize soil microclimate by maintaining more consistent soil temperatures, especially during cooler periods. The experiment was conducted in tomato fields at various altitudes in the Garhwal region, with and without BPM application. Results showed that BPM significantly improved soil temperature by 2-4°C compared to uncovered soil, particularly during the night and early morning hours. This temperature regulation led to faster seedling growth, extended growing periods, and higher tomato yield. BPM-treated plots produced significantly higher fruit weight, more tomatoes per plant, and better overall plant health compared to the control. The findings suggest that the adoption of black plastic mulch can be a sustainable solution for improving tomato production in the Garhwal Himalayas, where temperature fluctuations are a major limiting factor for crop growth.