How does a weather-based irrigation controller improve irrigation efficiency?

• A. It irrigates only at night using manual input.
• B. It adjusts watering schedules based on local weather data, reducing irrigation when not needed.
• C. It keeps a fixed daily schedule regardless of weather.
• D. It increases irrigation during windy days.

Answer: (B)

Using weather data to govern irrigation means the controller adjusts how much and when you water based on real-time local conditions. It looks at factors like recent rainfall, forecasted rain, temperature, humidity, and wind to estimate how much water your landscape actually needs. When rain has fallen or is forecast, the system reduces or skips watering, preventing waste and runoff. When atmospheric demand is high, it waters enough to meet plant needs, not on a fixed schedule. This alignment of water application with true plant demand minimizes waste, saves water and energy, and helps keep soil moisture in a healthy range.

Other approaches fall short because they don’t adapt to current conditions. A fixed schedule doesn’t respond to rain or drought, so it wastes water during wet periods and under-supplies during hot spells. Manual input or night-only watering misses the dynamic changes in weather, and simply increasing watering on windy days doesn’t inherently account for how weather affects plant water needs.