Hey everybody, I finally finished my first window farm (WF). It consists of an air lift and 2 rows of plant containers, with 5 containers in each row.

I put together a DIY guide, see it here (pdf).
I also made a Danish version of the guide (pdf), which includes prices and where to get the parts in Denmark.

I started figuring out how to build a WF, from scratch, about 3 months ago. I live in Denmark so buying a kit was out of the question. It took me a while to understand how the system was supposed to work, and then another while to figure out how I was going to build one myself. I had no experience working with the stuff needed to do this. Stuff like air pumps, tubes, and valves so it was all very confusing to begin with. I didn’t know anything about growing hydroponically either but ever since I saw the TED talk with Britta Riley, about a year ago, I have been interested in the project.

Now my WF is finally up and running and the plants grow bigger every day. So I want to thank this lovely community and the people behind the WF project for teaching me. It has been a lot of fun, and a little infuriating from time to time, when something just wouldn’t work the way I wanted it to.

I went through a couple of test systems, all of the air lift type, before landing on the one I am using now. At first I tried anchoring a tube on the bottom of a big water reservoir, but even though I knew this worked for others, I never managed to make it stable. The air from the pump kept flowing back into the reservoir, instead of lifting the water upwards. I then tried putting a small reservoir at the end of the row of plant containers. This worked very well; the reservoir had a tube in the bottom that went into a U-bend, which prevented air back flow to the reservoir. Unfortunately this setup forced me to reduce the number of plant containers I could have in a row, and I had to add water to the reservoir often, which was annoying. My current setup looks like this:

I put the reservoir, the air pump, and the U-bend below a shelf at my windowsill. There is a small gap between the shelf and the windowsill, where the tubes can get from below to above the shelf.

For reservoir I am using a 10 l (2.6 gallons) water container with a tap that is big enough for 2 tubes to fit into it. I made a plug of silicone sealant around the ends of the 2 tubes, to make a water tight fit (see info. box 1 on the sketch). To make sure the plug stays in place I wrapped some duct tape around the joint.

After leaving the tap of the water container each of the 2 tubes goes into a U-bend. *The U-bend needs to be at least 30 cm (12 inches) from top to bottom to prevent air back flow. (Thank you, Brian White, for sharing this information, the diagram you made really helped me a lot: http://our.windowfarms.org/files/2012/04/contest-with-u-April-7th.jpg)

After the U-bend there is a t-joint, where the water meets the air from the pump. I put a check valve on each of the 2 tubes leading the air to the t-joint, to prevent water reaching the pump (see info. Box 2 on the sketch).

In an effort to decrease the amount of plastic in my WF, and because I thought it would look good, I tried using coconut shells as plant containers. I hollowed out 10 coconut shells, cleaned them, and coated them on the inside with mineral oil to prevent them from absorbing water. I made a braided rope and nets for them to hang in. It looked really good but unfortunately the shells cracked. I think it happened because the shells I got were very old and dried out. I bought them all the same place but later on I tried with a shell bought at another place and it did not react the same way as the others. So I still think it could work with coconut shells, but I grew too impatient and my seedlings grew too big for me to do it all again with other coconuts. I turned to the well known plastic bottle instead, and I am very satisfied with the result.

I reused the rope I used to hang the coconut shells from but had to find another way to attach the new plant containers to the rope. I ended up with a kind of button on system which allows each plant container to be removed without dismantling the entire row. This highly modular system has the advantage that I don’t need net pots in the containers. I couldn’t find any net pots that would fit so I had to do without. If I do get my hands on some good net pots I will use them, though.

So I wanted to use coconut shells as plant containers, partly, because I wanted to reduce materials that could leak toxins into the water and plants. About this I have now come to think that the plant containers are actually the least important part. Most of the time, the water is in the reservoir or the tubes, so it’s more important that these parts don’t contain anything that will leak into the water. As the water drips into a plant container it goes straight through the clay pebbles and into another tube. Most of the clay pebbles that come into contact with the container are dry, as the water runs through the center part. I therefore don’t think the plastic bottles will be able to leak anything into the water, and if it does it will be minimal, compared to the reservoir and tubes.

These are the things I used to make my WF:

1    Air pump: Sera air 275 R plus. It has 2 outlets, a power regulator, and it comes with 2 check  valves

2    Water container with tap: 10 l (2.6 gallons). (It has the glass and fork symbol, which     means it’s intended for food contact; http://en.wikipedia.org/wiki/Food_safe_symbol)

3    Tube: 4/6 mm (0.15 inches/0.23 inches). I used about 6 m in total (19.6 feet)

4    Tube close up: It has the glass and fork symbol too.

5    T-joint and check valve: I used 2 of each.

6    Water bottle: 2 l (0.5 gallons). I used 10 of these.

7    Twine: 2 mm. (0.08 inches). I used about 10 m in total (32.8 feet).

8    Hooks: I used 7 in total (2 for each row, 2 for the water container, and 1 for the pump)

9    Spray paint: 1 can

10  Buttons: About 1 cm in diameter (0.4 inches). I used 40 of these.

11   Wire: 0.3 mm (0.01 inches). I used about 2 m in total (6.5 feet).

12  Power drill

13  Drill bit (4 mm – 0.15 inches) and screw bit (6 mm – 0.23 inches).

14  Hobby knife

15  Scissors

16  Belt punch

17  Duct tape

18  Silicone sealant

19  Clay pebbles (Leca): I used about 5 l in total (1.3 gallons).

20  Nutrients: Biosevia grow and Biosevia bloom

21  PH test kit (I didn’t use this to make the WF but it’s good to have afterwards)

22  Seeds, soil, egg shells, and egg tray.

23  Planted seeds in egg shells. This is how I grew my seedlings.

The essentials for making an air lift type WF: air pump, water container, tubes, valves and t-joints, grow medium, and nutrients.
The rest (tools, plant containers, plants) can be improvised.

After making the plant containers and assembling the system I transplanted the seedlings into the WF by carefully uprooting them, cleaning the soil from the roots, and putting them into the clay pebbles. The seedlings I have transplanted have all survived, it’s been about 2 weeks now. I also tried transplanting some cuttings from grown plants into the WF. One cutting was from a tomato plant and the others were from a basil plant. The tomato plant cutting had been growing in soil for a while and had become rather large. I thought it had grown too big to survive the transplantation and for a couple of hours it looked like it would die. Then it suddenly started getting better and the next day it was definitely on the mend. After 2 days it was back to normal. (The bend on the stem is caused by the way it has been growing before being put in the WF).

1 hour after transplantation

The next day it looks better

2 days later it's back to normal

The basil cuttings (3 in total) had different reactions: the first had grown pretty big in soil but it had no problem adjusting to the new environment. The second had not developed roots yet and for a long time, after putting it in the WF, it looked like it was dead. All the leaves fell of but I just let it be and now it has developed new leaves and looks like it will survive. The third already looked rather droopy when I put it in the WF and like the second one it dropped its leaves and looked like it was dying, but now it has developed new leaves too.

Besides tomato and basil I am growing chives, thyme, chili, and lettuce.
Row 1, from the top: chili, basil, thyme, chives, and tomato.
Row 2, from the top: chili, basil, thyme, lettuce, and chili again.Later I want to grow more lettuce and some strawberries, cilantro, mint, and pepper.

I don’t have a timer on my system at the moment but I will probably invest in one later on.

Pdf guide (English)
Pdf guide (Danish)

Thanks for reading and happy window farming.
Maj

I got my baby plants Friday, opened the box up to let them breathe, then set up the Windowfarm Saturday night.  I know it hasn’t even been 24 hours but the plants are droopy and I’m afraid they won’t make it.  I just moved (to Philadelphia) and can’t find the pH test strips, but do have the nutrients and started with 10ml and a full pot of water.  The window faces south but since it’s the ground floor of a townhouse it doesn’t get a whole lot of light.  Any thoughts/advice?  Thanks!

(First post as member!)

No under construction pictures, yet, but pictures of the space I have to work with. The plan is to work with the narrow window set on the far left to start.

Window Farm/Hydroponic Target Area

Microclimate/setup notes:

• There is a curtain rod that never gets used above the windows – I can use this to suspend the columns from.
• It gets full LIGHT for 80% of the day or more – there is no obstruction as we look over a harbour (Boston where the cruise ships dock/seaport) and we are the tallest point we can see.
• I can’t use the wider section because these are french doors that open to a balcony and the other small window area is a dedicated cat-viewing/perch area. (I’m amazed there wasn’t a cat there when I took this picture)

Materials:

• I already have full spectrum CFLs, conveniently, which partially factored into doing the second setup.
• I have two red and two blue LED grow lights from LED Wholesalers (12W, PAR38), already.
• The curtain rod above the windows wil be used for suspension. (I can hang from it and I’m about 130# – I wouldn’t want to do kipping pullups repeatedly on it, but is more than stable for this)

Plant selection for the vertical window garden:

• Catnip
• Spearmint
• Assorted kitchen herbs (chervil, thyme, lemon thyme, etc.) Rationale: Anything that comes in a plastic blister pack that has to be transported. I never use the entirety of these, they are $4USD per. Between plastic, the waste, the cost this is an ongoing pet peeve of mine.
• Specifically  NOT doing: Parsley, Cilantro, Basil. (These come in bulk and local)

Citrus Trees:

• I have 15 citrus trees (there are some in another room and some out of frame) and most aren’t doing too well (kaffir lime and calomondin orange are thriving, however). They used to be on the roofdeck of my previous place for the late spring->early fall and thrived. Wintering was always hit-miss, but this move was particularly bad. They’ve been yellowing leaves and have dropped between 50%->80% of their foliage. I suspect it is because this condo is so much moister/the soil doesn’t dry out fast enough and I’m seeing root rot. I’ve repotted them in fresh soil, but this has had very limited success.
• I’m looking at doing hydroponic citrus trees (marginally related to this community?) in the windows. Some of the trees have successfully fruited in the past. Since I’m acquiring the hydroton (per the materials sheet) for the columnar setup
• Advice needed:  ANY  experience anyone has doing this would be appreciated. I’m looking for setup thoughts (I’ve sketched out PVC exoskeletons for light rigging and water feeding on one end, to simple drip hoses on the other), nutrient thoughts (looking at Hoagland solutions as suggested by a few blogs – is there something better? One area I don’t have interest in is formulating my own nutrients for citrus trees)

Well, that’s it for now. This weekend will be materials gathering and whatnot until the hydroton and mesh cups arrive. Also, none of my friends that I’ve asked used disposable water bottles. Hah. Finding the water bottles is turning into the annoying part!

Hello, I discovered this website through TED, where I watched a talk by Britta Riley about window farming. As soon as I heard that window farmers have been able to grow strawberries that fruited for 9 months under low-light conditions, I was hooked. I am eager to get started on creating my own window farm.

I looked at the instructions for window farms 3.0, here, briefly. My first questions regard the use of plastic water bottles.

I did a quick search on the internet and found that plastic water bottles are typically made of Polyethylene terephthalate, commonly referred to as PETE or PET. Then, remembering hearing that plastic water bottles should not be reused, I did another quick search on what compounds are released when water is stored in plastic bottles for “too long” and what accelerates the rate of release of such compounds. The main thing I found was that dioxins are released by plastic water bottles, and doixins have been found to cause breast cancer in women, but I’m sure dioxins do not just affect women. I did another quick search on plant up-take of dioxins, and found that there is substantial literature regarding this issue as a health concern for humans. Not knowing the chemical structure of dioxins or their properties, I do not know what kinds of chemicals can be used to either chemically alter the dioxins into a safe form or to “sop up” the dioxins so plant up-take is reduced or eliminated.

My questions, then, are:

Is it safe to have plants growing in PETE bottles, with water constantly running through the bottles, extracting dioxins?

Is there a safer plastic to use than PETE, or another composition overall, for example glass?

Please do not hesitate to answer any of these questions (especially the last one) with something technically challenging (for example, using glass bottles would be difficult because cutting the glass would present a challenge). I will consider technical limitations at a later time.

Thank you!

Hi everybody,

I am working on a beautiful WF for a while now. It works pritty well with nice and stabel growth. I planted strawberry and pepper (and some more…)

What I am surprised about is the fact, that both plants have plenty of blossoms, however, both have only one single fruit. The other blossoms wilt and after that nothing happens. If anything happens, there are very small fruits which hardly grow.

What happens here? What can I do for more harvest?

Regards
Georg

My window farm is doing so well!  The plants have taken over my window.  I did a rough count and had 40 tomatoes growing!  Check out my video below.

http://youtu.be/lvDIZaK9GmI

Hi together,

yesterday I bought a small strawberry plant. I shook off all soil and put it into a cup, filled with expanded clay.

First the plant looked very well, especially this morning. During the day it went worse. Now the plant looks as below:

Does anyone know what I did wrong? I am thinking about too much water, maybe wrong ph-level (I didn’t check the actual level)?

Please help me from being guilty killing a strawberry plant.

Regards,
Georg

Hello windowfarmers.   Here are some photos of our window farm and check out our video.  If you have any questions check out my previous posts or leave a comment.  Last night I harvested some basil right from the window and made pesto.  Love it!

link to the video http://youtu.be/mT11bXaqhhc

and this is our spec on how our air pump lift works.

Hey Fellow-windowfarmers!

I’d like to share some pictures of the design and progress of our first ever windowfarm where we are growing peas, mini tomatoes and cayenne peppers So far, so good! More updates will follow as our plants grow.

As you will see, the basic set-up of the windowfarm includes; an airlift system using a pump, a nice green hose, a t-joint, two valves, a plastic white cereal container as a reservoir (3.5 litres capacity), 3 plastic white plant pots, two chains by which to suspend the pots from the curtain rail, plastic white tubing to allow the water & nutrients to drain down through each pot and some bbq skewers placed horizontally to keep the white tubing stable and to give the plants something to grab onto! Please feel to add your comments, feedbacks and tips!

Photos

Very special thanks goes to my boyfriend Dmitry for his engineering, design and building contributions. It is our windowfarm and I couldnt have done it without him .

Please forgive me if my netiquette is incorrect.  I’m new to this…

The inspiration:  I’ve been going to the same Christmas Tree Farm for 20 years.  It’s a sustainable farm, and we cut the tree ourselves, but we ALWAYS leave the bottom rung of branches on the tree.  Why?  Because then the tree completely regrows itself by next Christmas.  Every year I’m amazed that these tree stumps grow back as much as 10 feet in such a short time.

So I’m wondering what if instead of starting a hydroponic garden from scratch each season, what if we grafted our plants onto the branch of a “permanent” tree root base that provides all the nutrients for the plants without having to grow a new root and leaf system from scratch?  Wouldn’t this have the same effect?  10 times the growth?  Longer growing season?  Bigger yields?  Simpler irrigation?

I’ve heard that local hero, Luther Burbank, grafted 144 plant varieties onto a single apple tree!  So it seems like it should be possible.  But this is not my area of expertise and I don’t have enough time to research it myself this year.  Feedback?  Thoughts?  Suggestions?