Smart agriculture has emerged as a key solution to address critical challenges in traditional farming, including inefficient irrigation, excessive resource usage, delayed disease detection, and limited accessibility to modern technologies, especially in rural areas. The integration of the Internet of Things (IoT) and Artificial Intelligence (AI) has enabled data- driven decision-making, real-time monitoring, and automation in agricultural practices. This survey presents a comprehensive review of IoT- and AI-based smart agriculture systems reported in recent literature. Various system architectures, sensing technologies, communication methods, and AI techniques used for irrigation control, crop health monitoring, disease detection, and yield prediction are analyzed and compared. The survey also examines connectivity models, including internet- dependent and offline solutions, power management approaches such as solar-based systems, and user-access mechanisms like mobile applications, SMS alerts, and voice interfaces. Key challenges related to cost, scalability, data reliability, and rural deployment are discussed. Finally, the paper identifies existing research gaps and outlines future directions for developing affordable, scalable, and intelligent smart farming solutions, providing design insights for next- generation agricultural monitoring systems.