A smart greenhouse service enables precision farming with help of IoT devices (such as sensors and actuators) installed in a smart greenhouse. A smart greenhouse service collects information about both environment and crop-growth status, and then analyses the information to produce an optimal growth model for each crop. With the optimal growth model, a smart greenhouse service can maximize agricultural productivity and improve crop quality. In addition, it can enhance user convenience. To describe a smart greenhouse service framework, this Recommendation specifies requirements, a reference model, a functional architecture and interfaces for a smart greenhouse service.