Which sensor is used to monitor soil moisture to aid water scheduling?

• A. Soil Moisture Sensor
• B. Temperature Sensor
• C. Humidity Sensor
• D. Rain Sensor

Answer: (A)

Monitoring the actual water content in the root zone is what drives effective irrigation scheduling. A soil moisture sensor directly measures the volumetric water content of the soil, giving real-time data on how wet or dry the soil is and enabling precise decisions about when to irrigate. This helps prevent both overwatering and drought stress by triggering watering only when moisture falls below a target level. Other sensors don’t measure soil water content: a temperature sensor tracks how hot things are, which influences evaporation but not how much water remains in the soil; a humidity sensor gauges moisture in the air rather than in the soil; and a rain sensor detects precipitation to pause irrigation after rain but doesn’t tell you the current soil moisture status.