Modern agriculture faces the challenge of producing more food to meet the demands of a growing global population while minimizing its impact on the environment. To achieve this, precision agriculture has emerged as a transformative approach, harnessing cutting-edge technologies to optimize farming practices. Among these technologies, modern optical sensing has garnered significant attention due to its versatility, non-destructive nature, and high-resolution capabilities. This review explores the latest developments in optical sensing technologies and their wide-ranging applications in agriculture. We delve into the principles behind these sensors, their advantages, and their potential to revolutionize various aspects of farming, including crop monitoring, disease detection, soil analysis, and nutrient management. Additionally, we discuss challenges and opportunities for the widespread adoption of optical sensing in agriculture, highlighting the need for data integration, technological standardization, and farmer awareness. Through a comprehensive examination of the current state-of-the-art and future prospects, this review aims to demonstrate how modern optical sensing technologies have the potential to drive sustainable and efficient agriculture.