How to Make a Self Watering Planter

Introduction: How to Make a Self Watering Planter

In this instructable, I am going to show you how you can build a self watering planter. So lets get started!

Supplies

For this you need,

A 3d printer and filament to make the planter.

Water pump

Some electronics

Tools required for soldering

Step 1: Make the Planter and Reservoir

First, you need to make the planter and the water reservoir. To make mine, I used tinkercad. Its quite easy to make 3d models as well as simulate electronics in tinkercad.

You need to make your own planter to suit your plants.

Step 2: Make the Electronics

To make it easy to understand, I made the schematic using tinkercad circuits.

The circuit is very simple. When the soil in the planter is wet, its resistance is enough to close the transistor and power the relay. The water pump is connected to the Normally Closed contact of the relay. This is because when the soil is dry, the relay turns off. When the relay turns off, the water pump starts spraying water on plants till the soil is wet. I also added a led to show the state. Red means soil is dry and green means soil is adequately wet.

You have to make two electrodes of length 3 cm and place it 10 apart in the soil. The electrodes have to be placed in place of the potentiometer.

Important! You need to use a five volt relay or it won't work.

Step 3: Its Done + Updates

The build is complete.

4/4/2020Update: A person in the comments pointed out that this would work for less than a day on a normal 9v battery, so you can make some upgrades like:

  1. Using a 5v powerbank and a solar panel to power this.
  2. Adding some blue and red lights with a timer.

6/4/2020 Update: I tried using a 6A/H 12V Lithium ion battery with a 12 volt relay and now, it can last several weeks on a single charge

Indoor Plants Challenge

Participated in the
Indoor Plants Challenge

Be the First to Share

    Recommendations

    • Backyard Contest

      Backyard Contest
    • Fruit and Veggies Speed Challenge

      Fruit and Veggies Speed Challenge
    • First Time Author Contest

      First Time Author Contest

    7 Comments

    0
    StefanoS48
    StefanoS48

    1 year ago on Step 3

    Hi! I like your project! but I have a suggestion...why don't you reverse the relay logic? Let me explain myself. At the moment, a 9V PP3 battery (which is safe and simple to get) would last only a few hours (probably around 12 depending on the relay) as the relay is constantly draining juice to keep the coil engaged. If you use a PNP transistor (works when there is no power) instead of an NPN one (works when you power it on), you can activate the relay and the pump through the normally open pins at the same time. This will keep the relay ON only for a few seconds, then it will open the circuit for the next hours waiting for the soil to dry....and your battery will last days!! :) p.s. I think you will struggle to find a pump that works with your 9V battery...it is better if you find a 12V one (with an external 12V battery, maybe solar charged) or a mains one and you use the relay just to make it start and stop. The circuit is very similar to the one you made!

    0
    Gagan_Arora
    Gagan_Arora

    Reply 1 year ago

    Thanks,
    Actually, I was thinking of using a mains adapter but there was only a 9V battery in Tinkercad, so I used it. I measured the current required to power a relay and it was quite low(about 20 ma/h) so it should last pretty long with a rechargeable battery.

    0
    StefanoS48
    StefanoS48

    Reply 1 year ago

    If you use a normal PP3 battery and a 20mA/h it will last approx 7 hours. If you use a rechargeable one you are looking at about 40 hours in the best case. The adapter is a much better solution!

    0
    Gagan_Arora
    Gagan_Arora

    Reply 1 year ago

    Hi StefanoS48,
    I used a 12 volts 6 a/h Lithium ion battery along with a 12v relay and now it lasts for a few weeks with about 20-30 ma/h current draw.

    0
    StefanoS48
    StefanoS48

    Reply 1 year ago

    Great solution :)

    0
    eeh7474
    eeh7474

    1 year ago

    This is really cool. Thank you, StefanoS48!
    Do you have a pic of it working? Forgive me if I missed it on this page but, I can't seem to find the final product with a plant. Thanks again.

    0
    Gagan_Arora
    Gagan_Arora

    Reply 1 year ago

    Actually, I made this a while back and I don't have it now, so I used 3d modelling software to make it.