Window Farm - a Project Done in a Day!
I've been thinking about starting up my old hydroponics projects again and this weekend I just got the urge to do it. After some light research online (mostly on hemodlat.se; site in Swedish) I decided to build a window farm.
A window farm is basically a couple of plants hanging in your window. I only made three so, to call it a farm might be to exaggerate a bit actually. The thing about hydroponics is that you don't use soil as a growing medium. You use water (and air) instead. It is a really simple idea and it works great. However, you need to pump around some water and that takes some preparation. In this project, I have built an airlift pump system to transport the water to my plants.
Enough talking lets dive right in!
Step 1: Materials
To build this project you need some stuff... Here is what I used:
- PVC tubing, inner diameter 3mm, outer diameter 5mm (you have to measure how much you need, I used around 6m).
- T-connection for the tubes, 1 piece.
- A small air pump 12V I had lying around. I realize people usually don't have old scrap part air pumps lying around at home. If you don't, I recommend using a small air aquarium pump instead. These are usually quieter and have adjustments which can be a nice future to have. (something like this will probably suffice http://hydroponicsunlimited.com/product/air-pump-1-outlets-2w-3-2lmin/)
- A bucket (and lid) to store the water and nutrient mixture. Get a black one if you can. This will help keep out the light from your reservoir which will prevent algae.
- Pots! I chose these: https://www.bauhaus.se/planteringskruka-gra-15-5cm.html#full-description
- Some rope, leather and a chain to guide the water flow.
- A timer to control how often the plants will be watered.
- Oh! you will need towels, we are playing with water after all!
Step 2: Solder the Pump to a Power Supply (skip If You Use an Aquarium Pump)
Ok, this is pretty basic if you have soldered anything before. If you haven't, you shouldn't start with the electronics used near water (even if this is low voltage DC and pretty safe). Stick to the aquarium pump!
Step 3: Build the Air Lift Pump and Test It Out!
Let's get to it, building the pump!
How does it work?
As the name suggests the water is lifted by air in this setup. We start by creating a kind of siphon ( https://en.wikipedia.org/wiki/Siphon) to get the water from the reservoir flowing via the tube into the T-connection from underneath. At the perpendicular connection, we pump in the air. The air now lifts the water up through the tube. Not that much It may seem, I measured 40ml/15min (image 2). If we run the pump 15min every hour it becomes 40* 24 = 960ml/day and hopefully, that will be enough to make the herbs grow! Otherwise, we just increase the time we run the pump of course.
Test, test, and test!
To get this right you need to be patient and test a lot. If you like you can, of course, do some simple calculations as well. Make sure the fall hight of the water from the reservoir is enough (30-50cm should be enough). Also, make sure that when you have turned off the pump and start it again it doesn't push the air the wrong way and makes it bubble in the reservoir. This means it needs to be a higher fall height of the water inlet tube than the hight the airlift tube gets filled.
All right, that might not have been the best explanation but if this is unclear to you please leave a comment and I'll try to explain further. Or just ask someone who knows some physics for help!
Step 4: Building the Ampels (hanging Pots)
Good job, you got the pump working and now we can start to build the ampels!
You can, of course, buy amples if and use the pump to get started with your hydroponic window farm. However, if you like to build it yourself, as I did. This is how you can do it.
Cut and sow the leather strips
First a small notion of why I chose leather. Leather gives a very natural feeling to the ample. It also harmonizes very well when the pot gets wet and the color turns quite dark on the gray basalt. It is also easy to work with yourself.
My leather strips were cut in lengths of 50cm and width of 2.5cm. This depends on the pot though, so measure yourself. I then sow two loops on either side. Then moisten the leather and pushed it on to the pot. Done! Easy like 1, 2, 3 right?
Hang the pots onto the rope
I used small metal sprints (see image 6). These aren't optimal (from an aesthetic point of view) and I will exchange them for even smaller wood sprints when I can get my hands on some. When the leather strips are in place it is just to put the pot in place and you are basically done!
Add the chain!
Don't forget the chain. This helps guide the droplets and creates a beautiful sparkling stream along the golden chain.
Admire your work!
Take a step back and be proud.
Step 5: Plant Something in Your Pots!
Alright, I haven't really come around to do this yet but I'll keep you posted here when I do!
This project only took me 8-9h and in theory, it works. Hopefully, it will work in practice as well and give me some fresh herbs in my kitchen.
I at least filled the pots with leca (no soil!) so they are now ready.
I'll try to add some more pictures and videos as well when all is in place.
...To be continued...