Soil Moisture Sensor "freezes"

[alto777]

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Hints for outdoor soil moisture sensor

Have you considered making your own? They are not that hard to make. Simple thought, two metal probes with shrink tubing on the outside allowing it to be insulated until the tip is where you want it. Stainless Steel should work OK. Also be sure to use an AC or polarity switching circuit on the sensor.

HTH

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