Conventional irrigation and fertilization methods often lead to resource inefficiency and uncontrolled weed proliferation, which negatively impacts crop productivity and ecological balance. This study aimed to evaluate the effectiveness of a smart drip fertigation system integrated with Internet of Things (IoT) and powered by Photovoltaic (PV) solar energy in managing water-fertilizer delivery and its subsequent impact on Pakcoy (Brassica rapa L.) growth and weed vegetation. The research utilized an experimental design comparing the PV-IoT-based drip system with conventional surface irrigation. Parameters measured included soil moisture stability, water use efficiency, crop yield quality, and weed analysis (species diversity and density). The results indicated that the IoT-controlled system maintained optimal soil moisture levels, leading to a significant increase in Pakcoy growth parameters and most yield quality indicators (plant height, leaf number, fresh and dry weight, and ash content), while vitamin C content remained statistically stable, compared to conventional methods. Notably, the localized water distribution of the drip system substantially suppressed weed growth. The weed analysis revealed a significant reduction in weed density and a shift in species composition, where the smart system prevented the dominance of competitive water-demanding weed species such as T-Grass and Kremah, commonly found in conventional irrigation. The PV-integrated system was designed to operate entirely on solar power without grid dependency, supporting its potential as a sustainable solution for precision agriculture. This study concludes that the integration of PV-IoT in drip fertigation not only optimizes resource conservation but also serves as an effective ecological tool for weed management in vegetable cultivation.