Flexible wearable sensors have shown great potential in agriculture due to their excellent flexibility, biocompatibility, and long-term real-time monitoring capabilities. These sensors are used to monitor crop phenotypes and growth environment information in real time, providing key data for optimizing crop growth environments and improving crop yields. Traditional crop sensors are mainly rigid mechanical structures, which can cause damage to crop organs and have limited accuracy and biosafety. Flexible sensors, with excellent mechanical properties and biocompatibility, have attracted wide attention in crop phenotype monitoring. This review introduces key technologies in the preparation of flexible wearable sensors, including flexible preparation materials and advanced preparation processes. The monitoring functions of flexible sensors in crop growth are highlighted, including monitoring of crop nutrient, physiological, ecological, and growth environment information. The monitoring principle, performance, and pros and cons of each sensor are analyzed. The future opportunities and challenges of flexible wearable devices in crop monitoring are discussed from aspects such as new sensing theory, sensing materials, sensing structures, wireless power supply technology, and agricultural sensor networks. The review also summarizes the advantages and disadvantages of typical crop monitoring methods, focusing on the preparation of crop flexible sensors and their monitoring roles in crop growth. The review discusses the application scenarios of flexible wearable sensors in crop monitoring, including crop nutrient, physiological, ecological information, and growth environment monitoring. The review highlights the detection of crop nutrient information, water content, physiological information, and ecological information. The review also discusses the detection of crop growth environment information, including temperature, humidity, light, gas, etc. The review concludes that flexible wearable sensors have great application potential in crop monitoring and can provide important data support for the healthy growth of crops and effective management of agricultural production and resources.Flexible wearable sensors have shown great potential in agriculture due to their excellent flexibility, biocompatibility, and long-term real-time monitoring capabilities. These sensors are used to monitor crop phenotypes and growth environment information in real time, providing key data for optimizing crop growth environments and improving crop yields. Traditional crop sensors are mainly rigid mechanical structures, which can cause damage to crop organs and have limited accuracy and biosafety. Flexible sensors, with excellent mechanical properties and biocompatibility, have attracted wide attention in crop phenotype monitoring. This review introduces key technologies in the preparation of flexible wearable sensors, including flexible preparation materials and advanced preparation processes. The monitoring functions of flexible sensors in crop growth are highlighted, including monitoring of crop nutrient, physiological, ecological, and growth environment information. The monitoring principle, performance, and pros and cons of each sensor are analyzed. The future opportunities and challenges of flexible wearable devices in crop monitoring are discussed from aspects such as new sensing theory, sensing materials, sensing structures, wireless power supply technology, and agricultural sensor networks. The review also summarizes the advantages and disadvantages of typical crop monitoring methods, focusing on the preparation of crop flexible sensors and their monitoring roles in crop growth. The review discusses the application scenarios of flexible wearable sensors in crop monitoring, including crop nutrient, physiological, ecological information, and growth environment monitoring. The review highlights the detection of crop nutrient information, water content, physiological information, and ecological information. The review also discusses the detection of crop growth environment information, including temperature, humidity, light, gas, etc. The review concludes that flexible wearable sensors have great application potential in crop monitoring and can provide important data support for the healthy growth of crops and effective management of agricultural production and resources.