Carbon nanodots (CDs), a novel class of carbon-based nanomaterials, are rapidly emerging as promising agents in sustainable agriculture due to their unique physicochemical, optical, and biological properties. With sizes typically below 10 nm, CDs offer excellent biocompatibility, tunable fluorescence, high water solubility, and rich surface functionalization, making them ideal candidates for applications ranging from plant growth promotion to stress mitigation and smart nutrient delivery. This chapter comprehensively explores the synthesis strategies of CDs, including green, top-down, and bottom-up approaches, along with their characterization and mechanisms of interaction within plant systems. It further highlights how CDs enhance seed germination, nutrient uptake, photosynthesis, and biomass production, while also functioning as efficient nanocarriers for fertilizers, agrochemicals, and hormones. The role of CDs in alleviating abiotic and biotic stresses through antioxidant activity and gene regulation is discussed in depth. Additionally, recent advances in real-time plant monitoring, nanofertilizer design, and pathogen detection are presented, showcasing the multifaceted utility of CDs in modern precision agriculture. Despite their promising benefits, challenges related to large-scale synthesis, regulatory gaps, environmental fate, and field-level validation persist. This chapter concludes by addressing these concerns and outlining future research opportunities, positioning carbon nanodots as next-generation tools for climate-resilient and resource-efficient agricultural systems.