ESP32 - Automatic Irrigation System
This tutorial instructs you how to make an automatic irrigation system for the garden using ESP32, a soil moisture sensor, relay, and pump. In detail:
- When soil moisture is dry, ESP32 automatically turns a pump on to water plants.
- When soil moisture is wet, ESP32 automatically turns a pump off.
Hardware Used In This Tutorial
Introduction to Soil Moisture Sensor and Pump
We have specific tutorials about soil moisture sensor and pump. Each tutorial contains detailed information and step-by-step instructions about hardware pinout, working principle, wiring connection to ESP32, ESP32 code... Learn more about them at the following links:
- ESP32 - Soil Moisture Sensor tutorial
- ESP32 - Controls Pump tutorial
Wiring Diagram

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ESP32 Code
Quick Instructions
- Do calibration to determine the wet-dry THRESHOLD, see ESP32 - Calibrates Soil Moisture Sensor
- Update the calibrated THRESHOLD value in the code
- Open Serial Monitor on Arduino IDE
- Upload the code to ESP32 board
- See the result on Serial Monitor. It looks like the below:
Code Explanation
Read the line-by-line explanation in the comment lines of the source code!
Video Tutorial
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