Weather station - Soil temperature and moisture 🌻

[jcallaghan]

Objective

Monitor soil temperature and moisture as part of my #13 project.

Build an ESP module with a Dallas temperature probe and soil moisture sensor. The module should be housed in a waterproof enclosure and the sensors should be connected with a few meters of cable to allow for better placement. The soil temperature probe should be at a depth of 30cm.

Ingredients

• [x] D1 mini
• [x] Dallas temperature probe
• [x] Soil moisture ADC sensor
• [x] IP66 enclosure

Originally posted by @jcallaghan in https://github.com/jcallaghan/home-assistant-config/issues/13#issuecomment-624062276

[jcallaghan]

Research

• Instructables
• ESPHome
• Science Direct
• Soil temperature definition
• Photosynthetic activity was more highly correlated with soil temperature at 30 cm than with air temperature or soil temperature at shallower depths.
• Vinduino - Vineyard smart irrigation management
• ADC soil moisture discussion on Reddit
• Custom moisture board
• Sparkfun
• Pimoroni
• Soil mositsure meter for the Arduino
• Instructables Soil Hygrometer

[jcallaghan]

Buildout

Here is some pictures of building out the unit and ESP module inside the enclosure.

[jcallaghan]

Field testing

I placed the sensors in the soil for some testing. This is in a raised bed which won't be the final location. After pouring water onto the soil I did expect to see the moisture level raise somewhat so I will need to review why it didn't.

• [ ] Review moisture sensor

Air temperature: 14.7 °C Soil temperature: 12.2 °C