Soil Moisture Sensor Help Needed

[UjanDatta]

Hello, In the image the soil sensor probe, that has been circled, can that be used by connecting to an esp32 directly without the board on the left side?
If it can be can anyone share how to?

[ruilviana]

Yes, you can. But I think the sensitivity is too low.
You can use an ESP32 analog input using a resistor to pull up or pull down, depending on how you mount the sensor.

[docdoc]

In addition to the answer that @ruilviana has already given you (including the probable lack of sensitivity), the question is: why?
Why You don't want (can't?) use the adapter board? It gives you a useful digital output (the trimmer adjusts the threshold, and the LM393 compares the value with your threshold) in addition to the analog one.

[J-M-L]

Note that this sensor will be very quickly corroded, it’s good for a 5 minute experiment to check if there is water in a glass or not but don’t plan to use that for checking when to water your plants over the long term.

Look at capacitive sensors

[gilshultz]

I agree with @J-M-L on using the capacitive sensor. You can extend its life some by only powering it when taking a reading and reversing the polarity for each read. Good Luck.

[johnerrington]

@gilshultz

reversing the polarity for each read

My page here shows how you can do that

skillbank: Experiments and projects with an Arduino microcontroller

however I'd use more robust probes

[gilshultz]

Nice paper thanks for sharing!