During rain, the sensor plate elements are bridged by the rain water and hence this analog output gradually changes from 5V to 0V, based on the moisture level between the sensor pads. By this way, the ...

It isn’t that hard to make an electronic rain gauge if you have a steady source of power or you don’t mind changing batteries often. But [Matthew Ford] offers a third option: a simple d… ...

When the sensor detects that the moisture content is already below 30%, it sends a signal to the Arduino, which, in turn, activates a water pump to provide hydration to the plant.