What is "seasonal adjustment" in irrigation controllers?

Seasonal adjustment in irrigation controllers refers to the practice of modifying run times based on seasonal weather conditions. This involves adjusting the amount of water applied to plants in response to variations in temperature, humidity, and rainfall that occur during different times of the year. For instance, during hotter months when evaporation rates are higher, the irrigation schedule may require longer run times to adequately meet the plants' moisture needs. Conversely, during cooler or wetter months, irrigation may be reduced or even paused to prevent overwatering. This approach helps to ensure water efficiency and prevents plant stress by aligning irrigation practices with the seasonal climate patterns.

The other options, while they may involve considerations in plant care or irrigation practices, do not accurately reflect the meaning of seasonal adjustment within the context of irrigation controllers. Changing plant types does not directly relate to adjusting the irrigation schedule, and installing new equipment or adjusting plant spacing does not inherently address the variable water needs based on seasonal weather changes.