On-farm inoculation trials have been conducted to evaluate the potential of Bacillus subtilis NRRL B-30408 in respect of plant growth promotion, for two consecutive years, under rainfed conditions at a mountain location in the Indian Himalayan Region (IHR). For this, one cereal (Oryza sativa) and two millets (Eleusine coracana and Echinochloa frumentacea), were used as test crops. Observations were recorded in terms of plant growth, yield, chlorophyll content, and root colonization by various groups of microorganisms. Positive influence of bacterial inoculation on all the three crops, statistically significant in case of most parameters examined as compared to untreated controls, was recorded in both the years. There was a significant increase in chlorophyll concentration in leaves of inoculated plants. While the bacterial inoculation stimulated the free living bacterial and actinomycetes populations in the rhizosphere, the fungal population was somewhat suppressed; indicative of the antifungal property of the inoculant. The treatment also enhanced the colonization of arbuscular mycorrhizae (AM), and the endophytes associated with the roots. In conclusion, the plant growth promotion, recorded as a result of microbial inoculation, is attributed to the microbial shift in the native microflora of the rhizosphere. Based on the results of this field study, B. subtilis NRRL B-30408 can be proposed as an efficient bioinoculant for the hill crops, grown under rainfed conditions of the mountain ecosystem. The main aim of this study was on farm demonstration of the microbe based technology with peoples' participation, with a view of adoption of the technology by the farmers.