Soil Acidity Logger (2023)
Arduino UNO, waterproof enclosure (176 x 126 x 57 mm)
The Soil Acidity Logger (SAL) is cheap, open-source alternative for professional smart pH meters. SAL consists of an Arduino Uno, three pH probes for measuring soil pH, three pH sensors for processing data, an SD module for data storage and a time module for timestamping measurements.
SAL records soil pH values four times daily. By logging pH values separately from three probes, they can be strategically placed in different locations within the test site, allowing for precise comparisons. To retrieve pH values, one can simply remove the SD card and import the data into Excel for analysis.
SAL’s hardware was inspired by this tutorial, the code can be found on my GitHub page.
