Hi there,


Last month i posted my findings on using a cheap aliexpress plant sensor to monitor all kind of environment variables on the dutch Bonsai Empire forum (see www.bonsaiempire.nl/forum/bewateren-en-b...utomatisering-deel-1).

English is not my native language, but i thought lets also post it here, so i can share my setup to anyone who is interested. I will not describe all the technical details, i just would like to show what is possible when using a cheap plant sensor for our bonsai hobby.

So, last christmas i received the Xiaomi Flora Plant Sensor as a gift from my nephew.
This sensor can measure and transmit:
- Outside Tempurature
- Humidity substrate
- Light intensity
- Electrical Conductivity (EC) substrate

This sounds very nice, but there are several drawbacks:
1. Measurements are only transferred when a BLE (bluetooth low energy) connection is made (this will drain the sensor battery relatively fast).
2. You have to register yourself on the Xiaomi site and all your data will will be stored in the Chinese IoT (Internet of Things) cloud. This does not seem very attractive, because we all know how China deals with privacy.
3. You need a dedicated smartphone with the Xiaomi Plant App turned on 24/7 to collect/transfer the data to the cloud.

Solution:
Create your own hub by installing Home Assistant on a Raspberry Pi (mini computer), which then picks up the BLE advertising broadcast data (see github.com/custom-components/ble_monitor).
Every 60 sec. the Rasberry PI will read the temp, humidity, brightness and EC values via the BLE advertisement. All these values will be stored in a database.


Next step is to configue the limit values, which ensures that when these limit values ​​are exceeded, actions are taken.
Such an action could be, for example, that when the moisture of the soil is below 15% a whatsapp notification message is sent to my phone (see screenshot below).


These are the limit values ​​i currently configured for my Ulmus (i still have to fine tune these values).
Temp. for my Ulmus -> -3 <> 35 degrees
Moisture substrate Ulmus -> 15 <> 60%
Brightness during the day -> 3700 <> 60000 Lux
EC -> 350 <> 2000 uS / cm

But it doesn't stop here
There is also a dutch weather plugin (called Buienrader) for Home Assistant . This plugin will trigger a whatsapp notification message and lets me know when it's going to freeze outside within 24 hours.


Conclusion:
Do you absolutely need such a plant sensor to keep your Bonsai trees healthy?
No, but it is fun to play with and it could be helpful for Bonsai beginners who don't know when to water their bonsai.


My Ulmus with the Plant sensor sticking in the substrate


Some history graphs


The Rasberry Pi, i'm using

External links:
www.home-assistant.io/getting-started/
github.com/custom-components/ble_monitor
hacs.xyz/
www.callmebot.com/blog/whatsapp-text-mes...-from-homeassistant/

Cheers,
Ray

Thanks for sharing Ray!

Have you considered to automate the watering based on the values coming from Xiaomi Flora too?
I am considering to use an Arduino/Raspberry + humidity sensors + water pumps.

Razvan wrote:

Thanks for sharing Ray!

Have you considered to automate the watering based on the values coming from Xiaomi Flora too?
I am considering to use an Arduino/Raspberry + humidity sensors + water pumps.

No need to, because i'm using an 'ebb and flow' irrigation system based on Autopot Aquavalves. The system works solely on gravity, no electricity needed.
I posted this system on the dutch bonsaiempire site.
See www.bonsaiempire.nl/forum/bewateren-en-b...utomatisering-deel-2

It is in dutch but if people like, i can also make a post here in english.


Oh, and as you can see the tree is doing great with this irrigation system (picture taken a few weeks back)




Cheers,
Ray