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!

I was asked by Andrew Carter to do some testing of plant material to see if any unwanted molecules worked their way up the root system into the plant.  I haven’t received the samples yet, but I’d love to keep people up to date with the testing process and where I am at.   I will be posting again tomorrow with the details of the research I’ve done so far and the testing methods I plan to peruse.   I just wanted to introduce myself to the site, and open lines for any specific questions people might have!

In January I posted about my Plastic-Free AirLift Window Farm. I have since modified the materials a bit and successfully grew a bunch of lettuce and basil. I’m now growing mint and stevia — both seem very happy.

The initial version used stainless steel tumblers, mesh strainers, sisal rope, metal rope and crimps, a glass reservoir, natural rubber tubing, and organic nutrients (mostly bat guano). The only plastic part is the air pump.

Here are some modifications to the design:

• Replaced the smaller glass reservoir, which wasn’t tall enough to push the water up, with a 12″ high stainless steel container.
• Replaced the mesh screens, which didn’t leave enough room for the roots, with sink strainers.
• Replaced the bat guano nutrients, which got really slimy after a week or so, with fish emulsion.

And here’s a new image of the window farm and its gourd-based companion, currently in-progress.
More images and video can be found @ jennaspevack.com/windowfarm

Window Farm (Plastic-Free)

I’m attempting to build a version of the Airlift Window Farm without plastic parts.

The initial version uses stainless steel tumblers, sisal rope, metal crimps, a glass reservoir, and natural latex tubing. The only plastic part is the air pump. Everything was purchased fairly inexpensively (mostly on the Bowery in NYC).

You can find images of the project in progress HERE.

If I can get this one to work, I will build a second system next to this one using Chinese bottle gourds, coated in beeswax (see diagram). We’ll see.

PROBLEMS:

1. I’m currently having problems getting the pump to push the water up the airlift tube. I’ve noticed others have had this problem and see that Britta posted some suggestions, which I tried– but they haven’t worked. The air forced into the air lift tube doesn’t seem strong enough to move the water up vertically. It goes for about 6 inches and falls back down again. It also makes a loud bubbling/spattering noise. The pump tubes are dry and the air lift tube is fully submerged and mostly straight. I have an ActiveAqua AAPA7.8L pump. — ANY SUGGESTIONS?