Objective: This paper presents a detailed selection of IoT technologies for the design of an ambient humidity monitoring infrastructure to control crop irrigation. Methodology: The prototype design was supported by previous studies carried out by the authors and tests in 2019 at Finca el Porvenir in Cundinamarca, Colombia, in order to determine the best option to implement in the field through the use of Python software, and elements such as Raspberry Pi and the TTGO development board. Results: To determine the functionality of the software and hardware of the system, different static tests of the prototype were carried out by monitoring humidity and ambient temperature by means of the DHT22 sensor, whose information is sent from a transmitter node to a receiver node in a concentrator to later save the information in a database and, finally, to obtain graphs of the behavior of the relative humidity, temperature, and the actuation of the control element (solenoid valve). Conclusions: With this information it is possible to demonstrate the effectiveness of the prototype, the possibility of remote connection with the LoRa protocol and the handling and management of information from different crop areas through the GUI on the Raspberry Pi, generating a low-cost solution for access by small and medium producers in rural areas in Colombia.