This Gravity: Analog Soil Moisture Sensor For Arduino reads soil moisture. A low-tech tool ideal for urban gardens or pet plants, it’s a must-have for connected gardens. Using two probes, it measures resistance—more water means less resistance (better conductivity), dry soil more (poor). It helps remind you to water indoor plants or monitor garden soil moisture.

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1. Example Code for Arduino-Soil Moisture Sensing

This article guides you through setting up and coding an Arduino soil moisture sensor, offering hardware and software preparation, wiring diagrams, and sample code to accurately monitor moisture levels in soil.

Reference

Specification

Parameter	Details
Power supply	3.3v or 5v
Output voltage signal	0~4.2v
Current	35mA
Pin definition	Analog output(Blue wire); GND(Black wire); Power(Red wire)
Size	60x20x5mm
Value range	0 ~300 : dry soil; 300~700 : humid soil; 700~950 : in water