I’m strugeling with my soil moisture sensors (version 2,0). I didn’t get stable readings. See print screen. I already put a 1 M pull down resistor in, but that didn’t help. I want to make the garden water system automatic, but this isn’t going to work.
You have not provided enough information to get any help with your issue. There are several ways to measure soil moisture. I built one that is battery operated with a range of 30m. I used MySensors with a RFM69 radio and a Motenio M0 board.
Found the problem. I’m using a ESP32 and connected the sensor to GPIO35. In the YAML code I copied the pin was A0. I changed that, but for some reason it was back to A0 again. So I was measuring with a not connected port. I have a constant reading now.