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My First WF’s Progress

12:37 pm in Uncategorized by Andrew Dodd

This is the buttercrunch lettuce that I started from seed.  The hydroponics store gave me the fiber cubes to put them in.  I’m not sure if I’m supposed to take them out of the cubes soon or not.  It seems like they may retain too much moisture but I’m not sure.  I put them in a paper towel, in a dark warm corner on the night of Dec. 1st.  They had germinated enough to plant in the fiber cubes on the night of Dec. 3rd. They were given only plain water until Dec. 6th, then I added a 50% concentration of the recommended nutrient dose.  On the morning of Dec. 10th I added another 50% concentration to effectively bring the concentration up to 100% or the recommended dose (with a little error I’m sure for evaporation and such). Now its the morning of Dec. 11th and they’re already this big.  We’ve had some really nice sunny days for December which has also helped them out I believe.

by Tony

Strawberries-9 Months, New WF & First Snow of the Year

6:16 pm in Completed Window Farms, posts with pitcures! by Tony

Here we are at the first snow the year and my strawberry Window Farm is still going.  The three strawberries in my original WF on the left are 9 months old.  To the right is a new window farm.  The resevoir on this is a recycled cat litter jug and holds about 2 gallons.  The peas on the bottom are 32 days old and the bib lettuce in the middle are 26 days old.  Nothing is on the top yet.

First Snow of 2010

 It’s interesting that during the summer, the gallon resevoir on the strawberries needed to be topped off ever few days.  In the course of a week I would use about an extra gallon of water to top it off.  Now with the change of season and less light, during the week only a pint is needed to keep it topped off.  I have no supplemental lighting yet.

With the new WF I went and bought a Petco 9904 air pump that has the 4 outlets so I can supply air to both units.  In the second WF I am using a variation on my original Tee air pump design.  The difference in this one is the 5″ of hose that is coming out of the bottom.  It is hard to see, but this short extension also has smaller hose shoved in it.  You can see the plumbers tape in the hose that is holding it in place.  With this restriction, I seem to get better nutrient flow up the hose and less air bubbling back through the bottom.   The Petco pump has a variable output and I get plenty of flow with it set to its minimum.

Variation on Tee Air Pump

Happy window farming!

Vegetable “Flushing”

9:42 pm in Getting Started, Materials and Resources, Nutrients, Plants, Projects in Process, questions, Seeking Advice, Starting Seeds, Uncategorized by Andrew Dodd

Hey everyone.  I just built my first airlift windowfarm using the V2 instructions on the home page.  There is a local hydroponics store in my town so I was able to get all of the stuff I needed from there.  They pointed me towards some nutrient solution called Envy Part A and Envy Part B.  I had initially planned to get all organic nutrients since I will be growing vegetables to eat, but it was just too expensive.  Anyway, I’ve read some about “flushing” before harvesting the vegetables, and the guys at the hydroponics store offered some flushing solution, but I was wondering if just flushing with water for 7 days would work as well.  I don’t know that much about flushing and hydroponics so any information would be nice.  Thanks!

What’s the best way to germinate seeds?

9:00 pm in Uncategorized by Mickey T

Hi I’m Mickey and I’m building a window farm for my senior project. My kit came with butter crunch lettuce, romaine lettuce, basil, and rosemary seeds. I’m looking for an effective and easy way to germinate them before I put them in my window farm. I can find the instructions for constructing the whole window farm system but can’t locate the instructions for germinating the seeds. I remember something about putting them in a mixture of water and hydrogen-peroxide, but I can’t recall for how long. Thank you for your help.

by britta

Clay pellets and root growth

4:01 pm in environmental impact, Materials and Resources, Nutrients, Nutrition, Plants, posts with pitcures!, questions, Version 1.0 Reservoir System, Version 2.0 airlift system, Version 3.0 Modular Airlift Columns by britta

Plants roots are suspended in clay pellets so that we can run a liquid nutrient solution over the roots without leaving them in a bunch of soggy rotting muck.

Roots bathed in liquid nutrients grow into compact hairy root networks, rather than long big roots you find in soil where plants are out searching for water below ground. The hairs  grab hold of droplets of the liquid nutrients and grow into the porous cavities of the clay pellets to find tasty little juice pockets waiting for them even when the pump is turned off.

Dandelion green roots growing around and into clay pellets

The clay pellets are a great match for drip irrigation because they hold just the right amount of this stuff around the plants’ roots. No killer sog because, like rocks or pebbles, they shed water. But way better than rocks because they hold just a little bit of moisture close by for the hairs to reeeeeach out and ahhhhha get a little sip when they need it.

Clay pellets provide no nutritional value for the plant; it all comes from the nutrient solution. However, they are not made of lava rock, which would react and change the chemical composition of the nutrient solution. They are “inert,” meaning they don’t react.

Clay pellets shed water like pebbles, but their porous interior pockets hold little droplets of liquid nutrients for plants' root hairs to find

I like them because they can be reused, so I don’t have to add to the landfill with every crop. You can clean them and dip them in boiling water between crops to sterilize them.

Nothing is ever sacred and in the spirit of R&D-I-Y, it would be great to find ways of replacing clay pellets with something that was not shipped all over the world from Germany.

However, if you are new to windowfarming, I don’t recommend that these be one of the first things you start experimenting with substituting out.  Wait until you get the hang of dealing with nutrient solution first– there are plenty of other variables to change out as you get to know the microclimate of your window.

This is why we include them in the kits for new windowfarmers.


Substitutes for clay pellets

3:03 pm in Getting Started, Materials and Resources, Seeking Advice, Uncategorized by Jenny Sethman

We are trying to avoid extra expenses and were wondering if anyone has substituted the clay pellets for styrofoam peanuts or anything else?

Squash / Succhini pollination?

7:53 am in Plants, Seeking Advice by Trygve Henriksen

Does anyone have any experience with Squash / Succhini?

I have two of a ‘midnight’(miniature) variety in my WF.
(Picture in this post: )

Both have grown to decent size and bloomed many times, but I have been unable to get them pollinated.

Is there a special trick to this?

The “biofueled” pump and other news.

1:49 am in energy consumption, environmental impact, Help the project by testing this, Materials and Resources, Projects in Process, Uncategorized, Version 2.0 airlift system by Brian White

My experience with airlift goes back to fall 1983 when I worked in a pesticides lab in Ireland.  Distilling hexane. YUCK! Stinky boring job.

I was just amazed by the air bubbles going slowly through the cooling tubes on the distillation apparatus.  There was almost total hold up of liquid as the airbubbles slowly went through the clear plastic tubes. I am not sure exactly why but it reminded me of the “perfection” that is in the krebs cycle.

It was 4 or 5 years before I put this to any use in a coffee jar vacuum pump.  That was replaced by a combined tromp and airlift pump (the pulser pump) which also depended on almost exactly the same physics as you are using now in window farms! I found the pulser effect totally by accident.  If I had not found it, I am sure I would have done something very similar to the “biofueled pump” (without biofuel) next. In fact, I did use the pulser pump to pump water from a 50 gallon barrel in a very similar way way back then.   I just found the combination of tromp and airlift more adaptable so i stuck with it.

Anyway, I just put some videos on youtube that I think can help window farmers a lot.  I do not have a windowfarm but maybe you can adapt what I show and incorporate it into your experimental systems.

The bio fueled pump might be too slow for a windowfarm, but anyway, it is here  You can power it with an aquarium pump too and that is here (But then it is not biofueled anymore) It should be able to pump to 20 or 30 inches but you need the you tube to go down that much lower if you pump higher.

My little experiment with the t-joint and airlift pump is here

I did not produce any figures but if you see the videos, I am sure you can see that the  aquarium pump powered things pump fairly quickly.

The biofueled option has potential to spread the windowfarm concept to places where they have no electricity.

Yeast and sugar powered bio pump?

2:14 am in Uncategorized by Brian White

I do not know what flow this will give you but it does work. I made a simple pump that uses the gas from any fermentation to pump water.  Bread, beer or saurkraut would work. Of course it is totally experimental.  It is based on a coffee jar vacuum pump that I made over 2 decades ago. This uses pressure, and the old one used suction to do the pumping.

is the new pump and  the link below is to an animation of the old one

You can stack the pump stages to go higher.