The sketch first defines Arduino pin A0 so that it reads the moisture sensor value. It then defines Arduino pin 11 as output for the buzzer, and pin 13 as output for the LED.

For my totally-hypothetical at this point wireless soil moisture sensor project, I've been thinking about using supercapacitors.

Always under-watering or over-watering your plants? Wire up this Arduino-based sensor and save them.

You can throw a Raspberry Pi camera and OpenCV at the problem and approach it through software, or you can buy an off-the-shelf RGB sensor and wire it up to an Arduino.

The Pressure Sensor Module incorporates a material called Velostat with the Arduino. This material adds more resistance when more pressure is applied to the material. This module also uses the RGB LED ...

A competent Arduino implementation (SparkFun RedBoard) can get down to around 5mA from USB (if you remove the power LED) in deep sleep mode. The cheap Chinese ones do draw a lot more (20mA in deep ...