Buckaroo w/clue for soil - always 100% Moderators: adafruit_support_bill, adafruit

[jjligman]

Can anyone help me one this, I am totally new to all of this. I am trying us use the Clue with the Bonsai Buckaroo to make an automatic plant watering system. I used the code posted but it always says 98% - 100% when the nails are in soil, dry or not. The only way to get the % down lower is to remove the nails from the soil or unclip the alligator clips. When they are removed and separated it says 0% and then if I touch them together it jumps to 100% or so. Its as if it is not reading humidity or resistance but simply when or not the loop is being made at all and if soo 100%, if not 0%.

If anyone can help me resolve this it would me greatly appreciated. I am a complete noob to all of this stuff but really want to get into after this project and beyond. Right now I'm using this set-up for a school project and I'm lost.

Please let me know if you can assist.

Thanks!

Josh

[kevinjwalters]

How does it read if you have one nail out of the soil and then very slowly insert it? Have you experimented with the distance between the nails? Is there any chance you have a misleading dry top surface but one that's very wet and possibly loaded with fertilizer deeper down?

[liquidsquid793]

If you have the $$$ I would recommend picking up one of the Soil Moisture probes that use capacitive instead. I tried the buckaroo and it is fairly sensitive to fertilizer in the soil making an accurate reading needing to be adjusted for salt content. Soluble fertilizers are salts and will form a fairly conductive surface even with just moisture from the air. The stemma capacitive touch moisture sensors work very nicely, and seem unfazed with salt content.

You will need a Stemma cable that goes from the large format to the smaller and the sensor.

Note that to get these to work on the Clue, see an earlier post of mine with an adjustment on a delay for reading from the sensor to get it to work properly. I need to learn Git to start contributing there, just don't have the time.

Since I am working on a plant watering system (4 solenoids) for outdoor use, perhaps I can help a little. The problem is the day job sucks out my soul, so I don't get to work on this often.

[kevinjwalters]

Someone has added a helpful list of capacitive soil sensors to the answers to Stack Exchange: Raspberry Pi: Is soil moisture sensor corrosion normal? I'd be cautious on the generic ones as the circuit/component can vary.

I've been using a Seeed Studio Grove one for Instructables: Soil Moisture Sensing With the Maker Pi Pico.

[jjligman]

Thanks for the tips everyone. I think you all hit the nail on the head. I didn't even consider the feed and fertilizer in the soil. I didn't ask at the time but the person who brought the soil in brought Miracle Grow potting soil which is loaded with all of the above. I will be testing today on some plain dirt with nothing added and experiment with distance.

liquidsquid793 and kevinjwalters; thanks for the tips and links on capacitive soil sensors. Hopefully, I can find some extra time today to research these as well. I'm in the same boat with the day job liquidsquid793, between that and going back to school in my mid-thirties, motivation gets rough in tiny bit of free time left-over. This is part of a little group project at school but the adafruit site in general has captured my attention for a new hobby of building and development.