As agriculture faces mounting pressures from climate change, market volatility, and sustainability demands, smart contracts offer a promising digital solution for enhancing transparency, efficiency, and trust across food supply chains. This chapter explores the role of blockchain-enabled smart contracts in transforming agricultural transactions, with a focus on practical implementation rather than theoretical potential. Through detailed case studies, including food traceability, organic certification, and livestock veterinary records, it demonstrates how smart contracts automate critical processes such as payment release, compliance verification, and data logging. A structured, step-by-step guide is provided to help stakeholders, from farmers to policymakers, navigate the development and deployment of smart contracts in real-world agricultural settings. The chapter also addresses key challenges such as data reliability, legal enforceability, technical barriers, and integration with existing systems, offering insights into how these limitations can be mitigated to support inclusive and scalable adoption.