Introduction: Designer Indoor Plant Grower for Less Than 15$ #upcycle

In this tutorial, you will learn how to build an automatic indoor plant grower which:

  • is small enough to fit in any room
  • is stylish enough to fit in a living room
  • does not cost an arm (I've spent about 11€ (12$))

Mine is almost fully made from electronic parts you should be able to extract from your daily outdated or broken electronic devices (which is what I did).

If you like this project hit the vote button up in the right corner ;-)


  • a trash can, mine was a chromed inox 75cm high with a diameter of 30cm
  • a 30cm by 30cm wooden board, at least 5mm thick
  • some electric wires, mine was 5 meters of 10A maxi 1200W, bought in store for 3€
  • an electrical timer plug, bought in store for 3€
  • a light bulb femaleplug (mine is an E27 but you can pick an E14 if you prefer), bought in store 1€
  • a 20W LED grow light, "full range", special to grow plants (red + blue lights which makes violet light) E27 or E14 male according to your female plug below, bought on the web for 4€
  • a 5V to 12V DC alimentation, 5V is better since the fan doesn't need to turn full speed (which would make too much noise anyway), you can use an USB wall plug adapter since it takes input AC and deliver output 5V DC
  • a 8*8 or 12*12cm 12V computer fan, got it from an old Hi-Fi station
  • an emergency blanket, optional, if your trash is not chromed inox like mine, then it won't reflect light correctly in the inside, then you should cover the inside with the blanket so it will reflect light

EDIT 1: I started with a 10W LED but it seemed to be not enough so I moved to a 18W LED which seems to work better. The results with the 18W were good but not amazing. Since light quantity is one of the most important factor in plants' growth, I now moved to a 36W LED grow light. With its 12$ it's a bit more expansive than the 18W's 4$ but we'll see what happens with twice as light as it had until now. I'll keep you updated.

EDIT 2: WOW! The results with the 36W LED gave amazing results! A few months later I can now tell you I successfully got a lot of plants germinating and growing A LOT! inside this. From tomatoes seeds to blueberry seeds through lime seeds. With just enough watering, plants are just growing like crazy. Though, be careful not to water too much since the air flow is not as strong as outside. Just water when you see the leaves starting to go down or becoming a little wizened (every 2 or 3 day is enough but it will depend on your plants, air flow, etc).


  • a soldering iron

  • a steel saw

  • a drill (and an onion, the vegetable, yes, you'll understand)

  • some glue


mm: millimeters
cm: centimeters
V: volts
W: watts
A: ampers

Step 1: Build the Indoor Plant Grower

  1. Build the removable top with all the electrical stuff
    1. On the wooden board, draw the shape of your trash top and cut it
    2. Glue the wooden part to the top of your trash. On mine I only kept the circle of the trash's top and removed the top which was not necessary
    3. Once the glue is dry, on the wooden part, draw the hole for the light in the middle and drill it
    4. Draw the hole for the fan (8cm or 12cm diameter based on the fan you chose)
    5. Glue the light bulb female plug on top of the wooden board
    6. While the glue is drying, very carefully, without breaking it, open or cut the electrical timer. I chose to cut mine so I could access the wires in it directly, only keeping the top part which is making all the work we want ;-)
    7. Also, cut the male plug part on the AC to DC 5V converter to access the wires directly (be careful not to break/cut anything when you open it
    8. Cut the extremity of the output cable of the AC to DC 5V and identify the + and - cables
    9. At this point you should have everything open and ready to connect to each other. Follow the drawing
      Be very careful and at much as possible try not to have visible / touchable unprotected cables anywhere to limit the risk of electrocution...
    10. Test the circuit before continuing. If everything works as expected, continue, If not, debug ^_^
    11. Glue the AC to DC 5v on the wooden board
    12. Glue the timer on the wooden board
    13. Screw the fan on the wooden board (if it breaks it would be easier with screws rather than glue to change it ;-) ) The air flow should blow out of the trash and not going inside. Flip it if it is not positioned well.
    14. On the other side of the wooden board, apply glue everywhere and apply aluminium foil that you just stole from your mumy. Bad boy. Bad. Or a piece of the emergency blanket if you are going to use it.
      With that, the light will reflect even on the wooden part.
  2. Drill holes at the bottom of the trash so air can move from the bottom to the top, gently sucked out by the fan. If you don't, the fan will have a hard time extracting air from the grower. Plants need fresh air to avoid too much moisture which could brings rottenness. And it brings in more CO2. I mean, exactly like you need fresh air to survive with O2. Same for the plants ;-)

    You can drill or cut, based on the design you want.
    I used a tape all around to be sure to drill (almost) at the good height. And it was also allowing me to drill at regular interval or space.

    Then comes the hard time. Tip: If like me, you chose an INOX trash... beautiful but INOX, it is really hard to drill / cut it. But there is a technique that consist in drilling the hole with an onion in between. As you drill the acid juice of the onion will go down on the drill extremity and drilling will be easier.
    The best part is probably that tasty onion rings smell that it brings after the first hole ^_^

    Good luck with that, I surrendered after 12 holes to save my neighbors ears and sanity (and mine by the same time).

Step 2: Build the Movable Plate

In order to put and remove the plants from the inside of the grower, I've built this small system.


  • 3x1 meter of thin cord, I used the inside strand of 1 meter of a 7 strand paracord
  • a plate, usually used to ba placed under a planter
  • a small magnet


  • a very small driller (like a Dremel) or a sharp screw
  • scissors
  • some glue / tape


  1. Drill 3 small holes at equal distance around the extremity of the plate
  2. Put each string in each hole and make a double knot on the extremity so it will hold (see picture)
  3. Pull the 3 strings together on top such that all the 3 strings are straight and make a single knot using the 3 strings (see pictures)
  4. Glue the magnet to the big knot. Like that you won't be loosing this extremity every time by just sticking it to the side of the inox/iron grower ;-)


You can also use this technique on the biggest planter that can fit in your grower. In this case, the strings must be attaches to the planter and not to the plate for more stability.

If like me you are using it with multiple small plants then you should consider getting it closer to the light source by putting a flipped empty planter in the bottom of the grower.

Step 3: Plan the Sunshine / Darkness Periods

Using the timer you can now configure the lightening time and darkness time.

The timer I used is a mechanical one. It has 48 small switches, one for every half hour. When a switch is pushed, the electricity will be ON and when the switch is pulled the electricity will be OFF.
Then turn the circle without forcing until the arrow match the current time.
The switch on the side is made to bypass the timer so it is always ON. Be sure that this side switch is on the timing mode and not on the "always ON" position ;-)

Let me know in the comments if you used an electronic timer, I'm interested.

Most of the plants have 2 cycles which are :

  • Growing: around 18 hours of light a day
  • Flowering: around 12 hours of light a day

When you want the plant to stop growing, then just configure the timer for the flowering cycle and it should stop getting bigger and instead it should start making flowers ;-)

PS: I've seen that in some case it could also be interesting to change the kind of light bulb used but I guess it is not mandatory. Lightening time seems to be the most important.

PPS: Please understand that even if it should do it for most plants, this is not true for every plants. Some could need different temperatures or different lightening time. Some plants could even have more than 2 cycles.

Personally I am using this grower on my lemon trees and more generally to grow and get bigger and stronger plants during the winter when the lightening time is low. And also because it is too cold and not very accessible outside (living in the city anyway...).

Step 4: Automatic Watering / Pressurized Ceramic Cones

This part is very interesting since it doesn't need any electricity or complicated making.

This consists in a ceramic cone that is just enough porous to let the water be sucked out by the dirt not too fast. Since the ceramic cone, filled with water, is hermetically sealed, when the water is sucked out from the cone to the dirt, it creates a small depression in the cone's tank. Because the cone's tank is linked to a bigger tank of water with a small cable, the depression will drive some new water from the big tank to the cone's tank.

Please watch the pictures of this step in the order to understand how to use it correctly.

Drill one more very small hole in the lid of the tank, so its pressure will remain ok even when the water is sucked out from it.
The goal of the lid is to avoid anything to get inside the water, like moskitos.

If you let the big tank of water too long without refilling it (let say a few days), you may have to refill not only the big tank but also every cone's tank.


Now you can leave your plants for a few days (probably a good week or more) and it will still be watered, depending on the big tank volume. I used a pretty small one but it would work better with a 2 or 3 litters (or more) if you have one.

Look for "spike tender automatic waterer indoor plants" and you should find what I'm talking about for about 2€.

Step 5: Ma Gad, That Smells!

If you grow plants that smells a bit too much, like mint or basilic, it could be interesting to add a piece of carbon filter in the inside, of the hole of the fan. You can buy on the internet or at your hardware store some small thin squares of carbon filter. Then you just need to cut it at the good format and stick it.

The air will go through the filter which will keep smell. Change the filter when it does not work anymore.

Step 6: Hope It Helped

Send me the pictures of your growing cabinet below if you used this tutorial ;-) Can't wait to see what yours looks like!

Please vote for this tutorial for the "Indoor Gardening Contest" it would really help me out ^_^"

Have fun with your plants!

Indoor Gardening Contest 2015

Second Prize in the
Indoor Gardening Contest 2015

Make It Glow! Contest

Participated in the
Make It Glow! Contest