See video for example of why we need this.
Step 1: Build-Moisture Sensors
We will use three such sensors and use a multiplexor to alternate reading between them without using more than one arduino analog port.
While we will include a circuit board diagram, we recommend building the circuits on a breadboard first which will allow for both understanding and debugging.
Each sensor uses two nails, a 100 ohm resistor, and a 100 K-ohm resistor. We built a casing for each sensor with acrylic tubes, however this is not necessary.