This project presents a secure controlled-environment monitoring system that integrates IoT sensors, hardware-based cryptographic signing, and blockchain technology to ensure trustworthy environmental data collection. Temperature, humidity, and soil moisture readings are captured using low-power sensors connected to a Raspberry Pi. Each sensor reading is cryptographically signed using a Tropic Square secure element before being submitted to the Sui blockchain, providing data authenticity, integrity, and tamper resistance. The system is designed for periodic data collection and secure transmission and was validated through deployment in a greenhouse environment as well as extended testing in a controlled indoor setting. This makes the proposed approach suitable for smart agriculture and other controlled-environment applications where reliable and verifiable environmental data is critical. In the csv file we collected all relevant data, signatures and blockchain costs along 12 days (from January 12th, 2026 to January 29th, 2026). The system was deployed in Greenhouse and controlled environment at University of Salamanca facilities. There are 71 blockchain transactions (one each 4 hours).