Introduction: Automated Hydroponic Garden From Junk

About: An electronic designing firm

After seeing some trash items around the house, I decided to do something useful rather than throwing them away. The idea came to my mind was to make something that helps to grow plants inside our home.

Living in a world where most people use toxic chemicals for vegetables and fruits, is a hard and an unhealthy thing. Thus it’s hard to find quality vegetables without any toxins. So it’s a privilege if we have a space to grow some plants to consume. But today most people are living in urban areas. They have no space for gardening.

In here, I came up with a solution for the above matter, to build a hydroponic gardening system for indoors from things you can find from your trash bin. By following this Instructable, you will be able to make an Indoor hydroponic system and grow your own plants at your home.

There are many benefits of Indoor gardening. You can get fresh vegetables every day even in a cold weather. Also, gardening gives you pleasure to get rid of your busy stressful lives.

For any help regarding this or for further assistance for your projects, contact me HERE!!!

Step 1: Collected From Trash

Let’s see what I found from the trash bin. I got an old plastic container, used plastic coffee cups, and a broken LED lamp (LEDs are still good). The plastic box can be used as the hydroponic solution container.

coffee cups can be used as plant holders. And what about the LED lamp? Yes, I have another solution for that too.

DO NOT use paper cups for this. Use only plastic cups.

We can combine some electronic components and make a smart indoor gardening system. LED lamp can be used to provide light during night times to accelerate the growing process.

Let’s get started. Do not forget to find a cutter knife and a pen.

Step 2: Planning

As I mentioned earlier, coffee cups can be used as plant holders. About 10 years ago I tested a method of growing small plants on wet cotton. It’s time to use it again. So, find yourself some cotton balls.

My plan is to make some small holes in the bottom of the coffee cup to absorb hydroponic solution and place a cotton layer inside the cup. Roots will grab the cotton layer and make the plant strong.

See above images for the 3D model.

I thought to place about 6 cups inside the plastic box to leave space for plants to grow. It helps to absorb the sunlight by every plant evenly.

Step 3: Preparing Cups

Take your plastic cups and keep it upside down.

Make 3 or 4 medium size holes at the bottom of the cup. This will help to absorb the hydroponic solution to cotton.

Further, this facilitates the roots to come outside the cup and absorb nutrients itself.

Now place a 2cm thick cotton layer inside the cup. Do not press down the cotton layer. Keep it soft and relaxed.

Step 4: Cup Holder

Now we need something to hold the cups inside the plastic box. See what I found, a piece of foam board. We can use this as the cup holder. But how?

Cut a square shape that fits the opening of the plastic box.

Now measure the distances from edges and mark guidelines to draw 6 circles for cup holding holes.

Measure the diameter of your plastic cups and spread the 6 circle all over the foam board.

Mark the center points for the circles.

Step 5: Cup Holder: Part 2

Find a compass and make the distance between arms according to the radius of plastic cups.

Scratch circle shapes on the foam board using the compass. This will be an easy method rather than cut circles directly with a cutter knife.

After scratching remove the circles with a cutter knife.

Now you have a nice cupholder like in the last image.

Step 6: Placing Cups

Place all cups inside the holes.

Apply some hot glue around each cup, to make them strong and stick to the cup holder.

Now you have a basic hydroponic gardening system.

But I will not stop here. Let's move to the next step.

Step 7: Light Sensitive Circuit

To provide light to plants during night time, the LED lamp needs to be turned on everyday. To avoid this I have planned to make a circuit which will automatically turn on the lamp when the light conditions are low.

Collect following items.

  • LDR
  • 1K resistor
  • 100K potentiometer
  • 7805 Voltage regulator
  • 2N2222 transistor
  • 2 X IN4001 diodes
  • DC jack base
  • Vero board

Step 8: Diagram

Solder the circuit according to above diagrams.

Make it as small as possible to place it inside the LED lamp.

7805 is a voltage regulator which regulates 7V-30V input voltage to 5V output. This makes our work much easier.

Solder the positive and negative pins of the DC jack base to the positive and negative pins of the 7805 voltage regulator.

You can see how I soldered it, in the last two images.

Step 9: Placing the Circuit

There are only 2 wires coming out from the LED lamp.

Solder them to the 2 pins where I have placed an LED in the circuit diagrams.

Place the vero board inside the LED lamp, in a way that the DC jack base and the LDR placed under the board.

Change the shape of the vero board if it's hard to insert.

Use the above images as a guide.

Step 10: Making Holes

To plug the DC jack and to take the LDR out we have to make 2 holes on the lamp surface.

Mark the exact positions of the DC jack base and the LDR. Melt the plastic using the tip of the soldering iron.

It will look like the above image.

Now, the LDR will receive light through the hole and turn on the circuit when there are low light conditions.

Further, this will adjust the brightness of the LEDs according to the lighting conditions.

You can change the sensitivity of this circuit by setting the potentiometer.

Check how it works.

Step 11: Connect Things Together

The first image shows the 3D model of my initial plan.

To connect the LED lamp to the plastic box, make 2 holes at the edge of the plastic box.

Tighten the LED lamp to the plastic box using screws.

The DC jack base and the LDR should be placed at the opposite side of the plastic box as shown in the last image.

Step 12: Making the Hydroponic Solution

The hydroponic solution contains the nutrients for plants. There are several methods to make a hydroponic solution.

But the easiest method is to buy a concentrated hydroponic solution bottle.

There are instructions on how to make it.

Keep in mind... DO NOT use chlorine water to make hydroponic solutions.

Step 13: Finalizing

After making the hydroponic solution, fill them until it touches the bottom of the plastic cups.

Our automated hydroponic garden is ready now.

Use a DC power pack to power up the LED lamp and the Circuit.

Place seeds inside the cup and see them grow.

Hope you enjoyed this Instructable. Cheers!!!


For any help regarding this or for further assistance for your projects, contact me HERE!!!

Sensors Contest 2017

Participated in the
Sensors Contest 2017

Green Electronics Contest 2016

Participated in the
Green Electronics Contest 2016

Indoor Gardening Contest 2016

Participated in the
Indoor Gardening Contest 2016

Remix Contest 2016

Participated in the
Remix Contest 2016

Trash to Treasure Contest 2017

Participated in the
Trash to Treasure Contest 2017