How to Make Soil Moisture Meter Using Arduino With Real Time Display

Hey guys in this instructables i will show you how i made this Soil moisture meter that comes with a display that shows the soil moisture details in real time!

Yeah yeah in real time, How cool is that!

I have few plants that i keep inside my room and mostly i forget to water them and the main reason being the inability to check hjow moist the soil is whenever i see the soil with my eyes.

And i dont want to touch and feel the soil and it is not a job of makers like me!

Kidding! Jokes apart now let me tell the actual reason.

Whenever i water the plant i dont know how much water i poured and why im saying this is depending on the environment you live in the water from the soil evaporates.

After i pour the water to the plant lets say it takes 4 days to not water the plant and in monsoon every week or every 10 days i can water them.

So the biggest question now is how do i know when to water my plants?

The answer i would say to you is SIMPLY BUILD THIS SOIL MOISTURE METER!

This is the most practical solution i would say, this was the major reason that made me to build this device.

Now let me tell you what this project does.

This is a plug and play device, all you have to do is connect the board to usb supply and insert the stick inside the soil where you have your plant.

In real time you can see the moisture content present in the soil, There is a text message that work in real time on the OLED display.

The body is 3d printed and is portable and i have given all the files below so that you can modify and use it as per your requirements.

This also works best if you don't have pot but planted the plant in the ground, Just insert the moisture sensor stick inside soil and there you go.

I have given all the materials and program to make this project so that you can build one for yourself and never forget watering the plants.

If you make it consider posting them in the i made it section here on the instructables.

These are the supplies that you will need to make this moisture sensor project

Arduino Nano

OLED Display

Soil Moisture Sensor

Flame Sensor( i will explain you why i chose this)

Jumper Cables

Arduino IDE

Programming Cable

Slicing Software

Hot glue and super glue

PLA Filament

3D Printer

The plant that you always miss watering on time!

After serveral trial and errors i came up with this design and the design for this project was completely done using Tinkercad

The first step whenever i make any project is decide how i want the project to be(lookwise), and this was the design i decided.

The design may look simple but it has a lot of features! It has a slot at the base that was inclined so that the sensor sticks on the soil even on the full moist conditions.

The OLED and soil moisture sensor comes with a standard size so you can print this model and start assembling without thinking about anything.

I have also given the slots at the sides of the frame where you can connect the USB cable to power the nano board.

There are 2 parts in total and i have given the STL files for both below.

Simply use the files and proceed with slicing, i have given the slicer setting on the images here.

Export the design to printer and use PLA filament in your chosen color.

The print wont take much time and there is no need to post process anything on the printed part.

After the parts are ready we can assemble the electronics inside this.

This is the circuit that we will be using to make this soil moisture sensor.

There are total 3 parts used apart from the nano board, i suggest you to connect the components using the jumper cables.

The first is the OLED module, second and third is the moisture sensor and the flame sensor(these both will be merged as one)

Instead of the amplifier board that comes with the moisture sensor replace the amplifier part with the flame sensor.

Just remove the LED and solder the moisture sensor terminals and you are now good to go.

Like always connect the positive and negative from both the modules to the 5v and Gnd on the Nano board.

Sda to A5 whereas the Scl to A4 from the OLED module.

From the amplifier board connect A0(Sometimes shows as D0) on the board to A0 on the nano board.

Connect the nano to computer using USB, Open IDE and upload the code given below.

There you go! the project circuit is ready and to make sure everything is working fine dip the moisture sensor inside a glass of water and you should see levels of water on the display.

Now as you have the circuit ready we can head over to giving it a good casing and we will see that now.

To begin with insert the soil moisture sensor to the slot provided at the bottom of the frame.

Then you can glue the amplifier of the sensor to the side walls of the 3d printed frame and allow to dry completely.

Next i will start sealing the arduino nano board to the base of the 3d printed base part.

You can either use double sided adhesive or hot glue for this, i used hot glue(not too hot) since we are dealing with PLA filament 3d printed part.

Later after the glue is dry, add the OLED and this is the part you need to take care of because if glue sticks on the screen it takes a lot of time to clean that so be mindful when gluing this.

I have given some extra space inside the frame so that all the jumper cables will easily fit in and still there will be some room left.

After all these are complete, Seal the top part using the Lid.

But before cross check the circuit by simply connecting the board to usb and checking if there are no miss connections inside at the time of assembling and gluing.

Here you can simply use the super glue to have a good and clean seal between these two parts.

Using this is pretty much fun i would say, all you need is a good battery backup powerbank.

I use 10000mah power bank, Just connect USB to power bank and the other end to the nano board and you can see the display message on the OLED screen.

Usually the number will be 0 and now the device is ready for using.

The spokes(stick of moisture sensor) is inserted in the soil and now you can see the moisure content inside your soil being displayed on the OLED screen.

I tried it on the pot and the ground and i was able to get good results from both of the conditions.

If you have indoor plants then i think this suits best because in the indoor the light is limited as compared to outdoors so that the OLED looks super bright and this adds aesthetics to your plant pot.

The power consumption is low hence you can expect the battery to run for a very long time.

This was all about this project, If you have any questions regarding this project im happy to hear it from you in the comments section.

Consider checking this video tutorial that shows all the steps that you seen above but in a much more detailed way.

I thought of adding LED lights to this device, But that would consume more power from the battery and it will impact the backup.

Adding LED wont serve a purpose in the other way!

Hope you will try to make this and share me your makes.

That's all for now, Have a great day and once you make this you will "never forget to water your plants "