The hardware is consists of an Arduino microcontroller (here an Arduino Uno R3) and a pre-wired soil moisture sensor module. The soil moisture sensor module , built around the LM393 comparator, gives ...

This is a simple arduino project for a soil moisture sensor that will light up a LED at a certain moisture level. It uses Arduino Duemilanove microcontroller board. Two wires placed in the soil pot ...

I'd probably use one module to run 5 or 6 sensors, conformal coated and buried. I'll do some shallow trenching for wires, and mark the sensor locations somehow so I don't mow over them.

My soil-moisture reading was in the low 700s in soil that had around 30 percent moisture (according to a comparison with a commercial soil-moisture sensor), and 661 in a drier pot.

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 ...