I've received the kit lately, and I have just plugged everything. I only need to water two plants, so I haven't plugged two sensors. Still the water comes from the four tubes. Does it mean I need to change the default program ?
Yes, you can stop water from two water outlets you don't need by modifying the program.
A0/A1/A2/A3 represent four outlets respectively.
If you don't want to use A0, comment out “Moisture_value = map（value1,590, 360, 0, 100）; delay(20)" and add "Moisture_value = 100", you can stop water from A0.