The soil moisture sensor detects the water content in the soil and sends a corresponding analog signal to the Arduino Nano. The Arduino converts this analog reading into a percentage value from 0 to 100%. This moisture percentage is then displayed on an OLED screen along with a smiley, neutral, or sad face indicator depending on whether the soil is adequately watered, slightly dry, or too dry.
Why Build This
Easily monitor soil moisture levels in real-time
Prevent plant root rot from overwatering
Get clear visual indicators on an OLED screen
Make indoor plant care simpler and smarter
Real-World Application
This system is used in precision agriculture, automated greenhouse management, and smart indoor gardening to maintain optimal plant hydration and health.
Skills You'll Learn
Reading analog sensor data with Arduino
Interfacing an I2C OLED display
Mapping sensor values to percentages
Basic electronics wiring and breadboarding
Safety Precautions
Ensure all wiring connections are double-checked before powering the circuit to prevent short circuits. Keep the electronic components away from excessive water splashes when watering your plants. Always disconnect the power source when modifying circuit connections.
Technology Tags
ARDUINO NANO
SOIL MOISTURE SENSOR
OLED DISPLAY
I2C
BREADBOARD
Frequently Asked Questions
This project uses the Arduino Nano microcontroller.
The OLED display shows a percentage and a facial expression: a happy face for sufficient moisture, a neutral face for slightly dry soil, and a sad face for dry soil.
Yes, you can integrate a relay module and a water pump to create an automatic watering system.
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