Will an Adafruit STEMMA Soil Sensor work on a EnviroGrow

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I was bought a Adafruit STEMMA Soil Sensor as a present (Adafruit STEMMA Soil Sensor - I2C Capacitive Moisture Sensor [JST PH 2mm] : ID 4026 : $7.50 : Adafruit Industries, Unique & fun DIY electronics and kits). I want to use it with a envirogrow, but the connectors look incompatible. The enviro grow is JST SH and the sensor is JST PH. I could use this PH to SH cable (4-pin JST PH to JST SH Cable - STEMMA to QT / Qwiic [200mm long] : ID 4424 : $0.95 : Adafruit Industries, Unique & fun DIY electronics and kits), but the envirogrow looks like 3 pin, and the sensor is 4. Am I out of luck ?

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Doesn’t look like it will work on the A/B/C sensor ports (I don’t believe those are I2C), but it will work on the Qw/ST port (you’ll need to add some code)

the Qw/ST port is basically just a fancy I2C connector, which means you can add things like I2C GPIO expanders, multi ports (like this) and/or daisy chain I2C breakouts (as long as they have different I2C addresses).

please note, I don’t have an enviro grow, so my knowledge on it ends at the spec sheet and diagrams. For the code you’ll need to check the adafruit website for the sensor you bought, and you may need to do some tweaking, since the grow uses microPython by default, and adafruit tends to only supply circuitPython code (they’re very similar, and sometime compatible as is, but not always)

ETA:
That sensor says it can be set to 4 addresses (bare, AD0 soldered, AD1 soldered, and both AD0 & AD1 Soldered)

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This is for a read about the different “standard” connectors: What is STEMMA? | Adafruit STEMMA & STEMMA QT | Adafruit Learning System. The “Stemma” is the old (big) connector, available in 3-pin and 4-pin variations (I2C is only available on the 4-pin version).

Adafruit switched a few years ago to the smaller Stemma/Qt, mainly for space reasons and dropped the 3-pin variant all together.

The moisture sensors of the EnviroGrow aren’t I2C devices, and therefore not compatible. But you can use the I2C-pins broken out on the left side (if you have the Pi-hat) or the QT-connector (in case you have the Pico-variant) to attach the Adafruit device.

From software side things are more complicated as @nox already noted.

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Thanks for all the info.I will order the envirogrow and play.

I have patched the python on the enviroweather before so hopefully can make this work.