Soil Moisture Sensor

A soil moisture sensor can read the amount of moisture present in the soil surrounding it. It's an ideal for monitoring an urban garden, or your pet plant's water level. This is a must have component for a IOT garden / Agriculture!

The new soil moisture sensor uses Immersion Gold which protects the nickel from oxidation. Electroless nickel immersion gold (ENIG) has several advantages over more conventional (and cheaper) surface platings such as HASL (solder), including excellent surface planarity (particularly helpful for PCB's with large BGA packages), good oxidation resistance, and usability for untreated contact surfaces such as membrane switches and contact points.

This soil moisture arduino sensor uses the two probes to pass current through the soil, and then it reads that resistance to get the moisture level. More water makes the soil conduct electricity more easily (less resistance), while dry soil conducts electricity poorly (more resistance). This sensor will be helpful to remind you to water your indoor plants or to monitor the soil moisture in your garden.



To ease the difficult of using this sensor, a Gravity Interface is adapted to allow plug&play. The Arduino IO expansion shield is the best match for this sound senor connecting to your Arduino. As this sensor can work at 3.3V which make it compatible with Raspberry Pi, intel edison, joule and curie.

Quick Spec

• Power Supply: 3.3 or 5V
• Output Voltage Signal: 0 ~ 4.2V
• Current: 35mA
• Size: 60 x 20 x 5mm
• Surface Finish: Immersion Gold
• Net Weight: 17g

Circuit Diagram

Example Code

//Editor: Lauren
//Date: 13.01.2012
//Version: 1.0

//Connect the sensor to the A0(Analog 0) pin on the Arduino board

//the sensor value description
//0 ~ 300 = dry soil
//300~700 = humid soil
//700~950 = in water
 
void setup(){
   
  Serial.begin(57600);
   
}
 
void loop(){
   
  Serial.print("Moisture Sensor Value:");
  Serial.println(analogRead(0));  
  delay(100);
   
}

Value Range

• 0 ~ 300: dry soil
• 300 ~ 700: humid soil
• 700 ~ 950: in water

Resources

• Product Page
• Product Wiki
• Schematic

Shipping List

• 1 x Moisture Sensor
• 1 x Analog Sensor Cable