Espruino in the garden

I have some stuff I've done that isn't documented at the moment:

Using Puck.js as a soil moisture sensor

On the nRF52 chips you can turn internal pullup resistors on for analog channels - so you can do pinMode(..., "input_pullup");analogRead(...);pinMode(...,"input") to get a soil moisture reading.

You could do the same for some other Espruino board but you'd just have to add an external resistor.

Controlling a solenoid valve

I'm just using a cheap 12v solenoid valve from eBay powered from an old 12v battery from a UPS, and then using a P36NF06L to turn it on and off - it's really easy and very low power.