Introduction: Smart Planter Box

About: Making stuffs is cool.

More and more people are looking into buying indoor plants, especially millennials. However, “Roughly 1/3 of all plants purchased die within a few months of being brought home”. Although one of the advantages of the indoor plants is they are low maintenance, people are still killing their plants over and over again. Unlike having an animal pet, the plants’ status and needs are not obvious to the owners and may be neglected.

Due to the reason that I always kill my plants, I try to make my own self-watering system for my plants to keep them alive. Also, the box will show you the status your pet plant. The objectives of this project are:

1. Save people’s time and money by keeping their indoor plants alive.

2. Intensify the positive effects such as mood improvement of indoor plants through forming bonding between human and plants.

Step 1: Parts

Parts list

  • Photon particle
  • DFRobot Capacitive soil moisture sensor
  • Adafruit TSL2561 Digital Luminosity/Lux/Light Sensor
  • Adafruit SSD1306 Serial OLED Screen,0.96"
  • 12V DC Water pump
  • Battery Holder(6V)*2
  • AA Battery * 8
  • Keyes 5v relay module

1. I bought particle maker kit but didn’t use the photoresistor included. Why?

Adafruit is more sensitive and can detect light range from 0.1 up to 40000+ lux.

2. Why did I choose the capacitive soil moisture sensor but not resistive one?

Capacitive sensor is providing greater accuracy in comparison with the old resistive soil moisture sensor. Therefore, the chance of overwatered and underwatered will be decreased.

3. Why did I have to use a relay?

I used a 12V water pump. Photon can only provide 3.3V. I tried to use photon particle to power up the pump but the voltage is too low to pump the water. To power up the pump properly, I use external power supply, so I need a relay to control the off/on of the pump. How to use the relay module:


  • Plastic bottle
  • straws
  • Tapes
  • Gorilla glue (for sealing)
  • Birch plywood
  • Wood glue

The reason of using straws, tapes and plastic bottle is that they are easy to get.


  • Laser Cutter
  • Box cutter

Step 2: Create the Housing

I designed a box to place all the component inside. One of the reason was that I could place the OLED and light sensor in the specific place. Another reason was that the original design included a space for soil and plant so I can have a unique planter box.

I used this website to create box design for laser cutter easily:

Then I cut out some space space (modified the image by using illustrator) for

  • Watering straw Wiring the soil sensor
  • Wiring external power supply, so I can change the batteries with break the box
  • Demonstrate the OLED
  • Light sensor to detect the light
  • Plastic bottle, so I can know when I have to add some water to the container and do it without break the box structure.

Step 3: Make the Circuit

  1. Photon
  2. Capacitive soil moisture sensor
  3. Adafruit TSL2561 Digital Luminosity/Lux/Light Sensor
  4. Serial OLED Screen,0.96"
  5. Water pump
  6. Battery Holder

I used the motor image represents the water pump in the drawing. The image was created by fritzing (, a useful tool to draw a clean circuit.

Step 4: Install the Self-watering Part


  1. Cut the plastic bottle
  2. Connect the bottle and water pump with straw
  3. Use glue to seal the hole

Step 5: Programming

Self-watering system

  • Detect the moisture every 1 hr
  • The water pump will working when the soil sensor is > 3000 and will work for 5 second


  • Lux < 30 (sunrise/sunset) : “z..z..z”
  • Lux > 2000 (midday), Moisture < 3000: ”:D What a great day!"
  • Moisture > 3000 : “:( I feel sad.”
  • Others: ”:)”

Step 6: Test and Assemble


  1. stick the main breadboard on the inside of the "back side wood", there is a hole for usb and wires for battery holders
  2. place the light sensor into the hole on the "top side wood" and stick a holder below it
  3. wire the soil moisture sensor from the outside
  4. stick the second breadboard(for OLED) on the inside of the "left side wood"
  5. try to stick the OLED display on the inside of the "front side wood" so we can see the display from the front sight of the box
  6. place the bottle, water pump, and the relay in the proper place
  7. use the wood glue to stick all the housing peace together

Test(didn't add water)

1. Adjust the light to see how the display demonstrate the content I design. (the display and light sensor are work perfectly)

2. The soil is current wet so I pull out the soil sensor to let the system read the number >3000 (too dry) to trigger the pump. The sound represents the water pump is activated. Also, the display show the content I design. (soil moisture sensor, relay, and pump are working!)