What is the role of sensors in a greenhouse ventilation plan?

• A. Measure soil nutrients only.
• B. Automate vent and fan operation based on temperature and humidity.
• C. Stop all ventilation.
• D. Replace human inspections.

Answer: (B)

Sensors in a greenhouse ventilation plan monitor air temperature and humidity (and sometimes CO2) and feed that data to a controller. The controller uses predefined targets and automatically opens vents or runs fans when conditions go outside those targets, and tightens or stops ventilation when they return to range. This automatic adjustment keeps the air exchanges timely, preventing heat buildup and excessive humidity that can invite diseases, while also saving energy by ventilating only as needed. Soil nutrients or other soil-focused measures aren’t what control the air exchange, so measuring them wouldn’t guide ventilation. Ventilation isn’t meant to be stopped entirely, and while sensors automate responses, human oversight and maintenance remain important to keep the system functioning correctly.