Here is a tested Arduino project that uses 3 sensor probes as water level indicator with 3 leds and one LCD display + a simple controller that turns on a motor when the water has reached the desired ...

The basement water tank level sensor is another simple (1-point level) float switch, added as a dry-run protector. Hermetically sealed-in-glass reed switches located inside the stem are ...

It runs on an Arduino MEGA 2560 PRO (or similar microcontroller) and supports a wide array of additional hardware including pressure transducer, water level sensor, flow meter, OLED display, and more.

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.