Plant Monitor Pet with Home Assistant 

M3x5mm Caphead Screws x4

40 colored male-female jumper wires

Soldering Iron 

3D Printer (Prusa CORE One+)

Arduino Nesso N1

SparkFun Qwiic Soil Moisture Sensor (Capacitive)

PIR Motion Sensor Module

Arduino IDE

Temperature & Humidity Sensor (DHT11)

M3x5mm heat set inserts x4

<html><body><h3>Plant Monitoring Pet with the Arduino Nesso N1</h3>This project explores building a plant monitoring device with the Arduino Nesso N1 that has an animated UI and reports sensor readings over Zigbee to Home Assistant. To watch along with this build check out the full <a href="https://www.youtube.com/playlist?list=PLbWlTd7TJ7bo">YouTube playlist here </a>, or watch on <a href="https://www.instagram.com/electronic_esoterica/">Instagram </a>. <h3>How It Works</h3>The firmware samples sensors at regular intervals and maps readings into mood states. Each state adjusts face expression, leaf pose and background animation. Sensor data is also sent over Zigbee for integration with Home Assistant. Mood States <ol><li>Happy (Soil in calibrated range, temperature/humidity normal): 	Upright leaves, glossy highlights, cheerful face </li><li>Thirsty (Soil below calibrated dry point): Drooping leaves, dry color cues </li><li>Soggy (Soil above calibrated wet point): Darker leaves, droplet animation </li><li>Cold	(Temperature below 10C): Curling and shiver animation </li><li>Hot (Temperature above 30C): Wilted posture with heat cues </li><li>Sleeping (Not in soil): Hidden plant, sleeping face </li></ol>Display Modes Modes are cycled with KEY2 which is on the right side of the device: <ol><li>PIR + Audio: Display wakes on motion, chimes enabled, sleeps after inactivity </li><li>PIR + Mute: Motion wake behavior, no chimes </li><li>Always On + Audio: Display always on, chimes enabled </li><li>Always On + Mute: Display always on, no chimes </li><li>Zigbee Only: Display off, timer wake for hourly Zigbee reporting </li><li>Hold longer than 5 seconds: Zigbee factory reset for re-pairing </li></ol>Buttons and Calibration Calibration is required because capacitance values vary by soil type, moisture level, and probe placement. <ol><li>Hold 0.5 to 5 seconds: calibrate wet </li><li>Double tap: calibrate air (probe out of soil) </li><li>Triple tap: calibrate dry </li><li>Hold longer than 5 seconds: reset calibration defaults </li><li>Single tap: wake behavior only (no calibration action) </li></ol>Calibration values are stored in RTC memory and persist through deep sleep cycles. Zigbee Integration The firmware exposes two Zigbee endpoints which are reported every 30s while awake and once an hour in deep sleep mode: <ol><li>Endpoint 10: Temperature (0x0402), Relative Humidity (0x0405), Power Configuration (0x0001) </li><li>Endpoint 11: Pressure Measurement (0x0406), repurposed for soil moisture in picofarads </li></ol>These endpoints are used because the SLZB-06 Hub Mode I was using doesn't support a soil moisture sensor. The "Pressure Measurement" can be renamed in Home Assistant to match. <h3>Building the device</h3>The full BOM, code and 3D part files can be found on GitHub at <a href="https://github.com/jimbruges/nesso-plant-pet">https://github.com/jimbruges/nesso-plant-pet</a>Printing the case parts can be done on any 3D printer. In this case I used a Prusa Core One+ with translucent PETG for its water and UV resistant properties. M3 threaded heat set inserts can be melted into the holes on the front side of the case with a soldering iron, then M3x5 caphead screws can be used to clamp the parts together. Make sure you insert the two button extension pieces into the case before putting any electronics in. The gallery below shows the wiring and assembly order: <div id="gallery"><img id="gallery" src="https://projects.arduinocontent.cc/80e56242-2021-4a34-81ee-7c7640e4cd6d.jpg"/><figcaption>The final build</figcaption>,<img id="gallery" src="https://projects.arduinocontent.cc/74a6ab4b-2f9d-4af2-85eb-bf3b00aa61a0.jpg"/><figcaption>Rear of the unit (with hole for temp sensor)</figcaption>,<img id="gallery" src="https://projects.arduinocontent.cc/097744e1-6a9c-465b-9de2-5e82aa9f5a3a.jpg"/><figcaption>All the components inside</figcaption>,<img id="gallery" src="https://projects.arduinocontent.cc/a58cb562-3453-4903-b53b-5a3b1f374fa6.jpg"/><figcaption>The Nesso N1 snaps into place</figcaption>,<img id="gallery" src="https://projects.arduinocontent.cc/addabfb2-a2d9-4123-bb99-d2fdaf0eb3f8.jpg"/><figcaption>The PIR sensor must be connected to 5V, GND and G2</figcaption>,<img id="gallery" src="https://projects.arduinocontent.cc/ca7dbf2c-6ffb-4e00-9ebe-fef52d8a23a6.jpg"/><figcaption>Heatset inserts (M3) inserted in front side with soldering iron</figcaption>,<img id="gallery" src="https://projects.arduinocontent.cc/efb32242-a7aa-4422-a5bc-34528e86a7d9.jpg"/><figcaption>All the assembly parts (3D printed shell and buttons, M3 caphead screws, M3 heatset inserts)</figcaption></div> </body></html>

Nesso Plant Pet Code Repository

3D Print Files

Plant Monitor Pet with Home Assistant

Build a low power plant monitor with a personality! This Nesso N1 project reminds you to water your pot plant with a friendly face and sends data over ZigBee to your Home Assistant instance.