My mistakes with the Pimoroni Enviro Grow

This year I got a Pimoroni Enviro Grow for my birthday. As a person who is structured enough to almost never forget to water the plants, my plants tend to live quite long and happy. Although, the problem is almost... I love the fact of gathering data with all kinds of sensors and apps, and most of it I throw out of the door at some point, but not this, I say to myself. Because this is useful.

To give you a bit of background information: I've played with Arduino's, ESP32, Raspberry Pi's and the Pimoroni Enviro + Air Quality HAT. Most of it needed some cable to upload a program or follow a very long tutorial with loads of examples. This was what I was expecting when starting this project.

First attempt

Let's get started, so I find my only USB to micro-USB with data somewhere in my cable nest. Label it, so it will be easier to find over two years. Connect the Pico to my Laptop and went online to find some documentation about this thing.

I followed the guide, setup Wi-Fi, make use of MQTT, didn't know what host to use, so I added the host with port. Everything was nice and easy. But it didn't work.

I opened Thonny, connected the thing up, looked through the code and saw that it used the port 1883 by default and that the host config didn't support setting another port. So I changed the mqtt.host:1883 to mqtt.host in the config.py and uploaded it. Now the board just blinked red a couple of times and quit. So I checked the logs by triggering the script from Thonny, and it couldn't find the Pimoroni libraries. That's when I realized I should've changed it via the web interface and not tinker around in the code.

Fixing everything

Instead of fixing the problem, let's start fresh. I went to the Upgrading Firmware page and followed the instructions how to re-upload the latest firmware. I redid my steps to configure it, except the port part in the host. And everything worked. I had values in the broker. At this point, I was done for the evening.

The next day, I realized I didn't get value out of it, because it was not providing me with feedback (I don't check my MQTT server every day). So instead of adding it to Home Assistant or a database with alerting, I opted for something simple. Let a program listen to the MQTT topic and check if any of the three sensors is below a certain threshold and is above zero. zero means it has no readings (no sensor attached). When that is the case, I push a notification to my phone with the host and sensor names that are below the threshold.

Future plans

1. Storing all the readings in a long term database, something that also works with my Home Assistant data
2. Get the extension cables, the cables are too short to have three plants attached
3. Add the pumps, but that will be a separate project with a lot more sensors to make sure the pumps don't run when there is no water