Moveable hanging windowfarm we made for demos

This demo model was all about portability. It has much in common with a standard reservoir setup, but we needed to be able to move it out into the main space so we could show people how a windowfarm works while also being able to put it back in the window most of the time so it could get light (and grow HUGE!!) .

This model came before the move to sewer pipe reservoirs. We used the same suspended tupperware reservoir technique we used in the first prototype that we built in my apartment’s kitchen window.

You can’t see it in this picture but the “plumbing” is detachable and can be moved separately from the plants. We suspend a tupperware reservoir above this windowfarm and use a bucket on the right at the bottom to recapture the liquid and house the pump. We drilled holes through the side of the tupperware container up top  and attached individual tubes to the reservoir (tricky plumbing!). The individual tubes dangle down into the top of each column. The “recapture” tube you see at the bottom attached to the bottom dowel drained into a 5 gallon bucket that also housed the pump (on the right, not shown). The pump in the bucket is attached by a long tube to the reservoir up top, closing the loop. 

We made it portable by creating a removable frame for the bottle columns. We hung one dowel rod from another dowel rod with tension cable, creating a loose hanging frame. Then we hung each strand of bottles from a dowel rod at the top using the fishing wire technique. There are holes in the recapture tube, into which we insert the tube at the bottom of each column. We tied the recapture tube to the bottom dowel with zip ties.

 It was so exciting to just pick the whole thing up and move it down the hallway! It’s light enough for one person to carry even with these big plants.

These plants were all started from seed in February. The lettuce loved the cool early spring. Look at how bushy that blackseeded simpson got (mid left). There are also cucumber (the yellow flowers at top left), okra (maple-looking leaves mid right) , green beans (top right) kale (bottom right) and cherry tomatoes (bottom left), jalepenos, and Japanese Eggplant (bottom right big leaves) in this system. The cherry tomatoes,  jalepenos, and okra are just now ripe in early August. Beans keep coming- super tasty, crunchy, and sweet. The lettuce went to seed and started tasting better about after about 2 months of churning out georgeous new leaves constantly when we picked them.  Aphids and a weekend when I left the pump off (OOPS!) killed the eggplant. The cucumbers were a real mystery. Like Marilyn and James Dean, they died a young tragic death after a short, but full life. Read their sad story here. Someone else please try cucumbers!

Britta and I finished the first window farm prototype in her kitchen window in April. The system includes a pump in a bottom reservoir which is on a timer, to pump about 3 gallons of water/nutrient solution up to the top reservoir. The liquid then drips through the columns of water bottles that hold the plants.

We’ve listed each component below, and some of the lessons we learned.

The main components are:

• Reservoir 1 (a 5 gallon bucket on the floor)
• Water pump (orange)
• Reservoir 2 (a tupperware container on a shelf above the window)
• Large diameter tubing going up to fill Reservoir 2 (orange)
• Small tubing to and from each vertical component
• Clamps
• Water bottles
• Net cups with clay pellets
• Covering for roots
• Fishing Wire to suspend
• CFL bulbs and covers
• Light Timer
• Air Pump
• Second timer for pump

Scroll down for more details about each component. We have listed each component and ordering information on this site.

Reservoir 1 is a 5 gallon bucket on the floor with water and nutrient solution

- 500+ gallon per hour pump of high quality which makes it quieter. You can go with a cheaper one if like this it will only turn on 3 times a day.

- There is a timer on the pump which turns on for 2 minutes every 8 hours. It fills Reservoir 2.

- Along with the pump, the reservoir also has an aquarium air bubbler in it to keep the water aerated or moving so it does not stagnate. This thing is a problem because it is loud. We should find quieter ones because it stays on all the time.

Parts in this area:

• 5 gallon bucket
• Water pump (500 gph)
• Timer for pump with at least 3 on/off settings per day
• Aquarium air bubbler and airline tubing
• Tubing that fits water pump fitting (to go to reservoir 2)
• Extension cord
• Nutrient solution mixed with water

Reservoir 2 above the window

- The reservoir is filled via the tube coming up from the pump in reservoir 1. The size of the tubing was determined by the fitting on the pump.

- The reservoir itself is a tupperware container we got at the hardware store. In the future we would look for something made out of thicker plastic so it is easier to put the plumbing connections into. This plastic was thin and difficult to drill clean holes into. Also, technically this should be an opaque container since nutrient solution should not be exposed to prolonged light, but we choose clear so we could see the nutrient level and color.

- We used brass pipe fittings to connect the tube to the reservoir. They included the barbed brass and yellow rubber you see on the right of this photo. You cannot see the other side of the fittings, where we used the female pipe fittings to tighten the connection on the inside of the reservoir.

- There are 5 tubes which come out of the reservoir.

- They are clamped down really hard so that the 3 gallons of water in the reservoir takes the whole 8 hours to drip through the system – so the plants are getting a constant drip.

- We’ve realized now that instead of clamping, the better solution would be to use much smaller tubing – probably 1/8th inch – to slow the water flow – instead of needing the clamp the tubes.

Parts in this area

• 5 gallon tupperware container with lid
• Shelf and brackets to mount container on above window
• Barbed connectors to connect reservoir to tubing to plants, rubber O-rings and aquarium sealer
• Clamps (although these might not be necessary if your tubing is much smaller than ours)

Water Bottles

- The five tubes from Reservoir 2 extend into the top water bottles.

- The water bottles are suspended by 15 lb fishing wire tied to simple hooks drilled into the top of the window.

- The plants are in net cups, in clay pellets, resting in the water bottles, which, because of the ‘eco-shape’, are the perfect size for the net cups.

- Some of bottles have their caps on, with some holes drilled in the caps for the water to drip through. Another design we experimented with here has plastic martini glasses duct-taped to the bottles which have had their tops cut off.

- The water drips down through each plant and then to this tubing at the bottom, which brings the water solution back to the bucket reservoir.

- 6 100 Watt CFLs from Home depot in normal sockets. This may be overkill. However, in general the closer you can get the lights to the plants the more growth you can generate.

- Light Timer with 5 sockets goes on once a day and turns off once a day

These are some of the things we would change in the next version:

• Find better plumbing components
• Ian suggested using a chin up bar to suspend everything from at the top of the window to not have to drill the hooks
• Gabriel points out that a cheaper alternative to a chin-up bar might be some threaded pipe from the hardware store. They sell metal pipe cut to length and threaded on the ends, which screws into plates that are screwed onto the window frame. So some holes in window frame, but only in two places vs. a series as with hooks. Very strong.
• Remove the reservoir at the top and experiment with the pump so the water can go directly to the plants
• Play with the lighting design so less light bleeds into the apartment and out the window
• Find more flexible tubing for the bottom so that there’s not that large tube going to the reservoir
• Use containers other than water bottles
• Find a way to use coconut coir so it doesn’t clog the system
• Look into using copper
• Pump- cheaper? Non-electro?
• Air pump- quieter? Non-electro?
• Tubing adapters- easier?
• Reservoir 2 attachments
• Root covers- elegant?
• Containers- alternatives, less labor
• Wiring- Less messy
• Clamps- cheaper
• Suspension- Less invasive, more stable
• Aeroponics?
• Microgreens setup?
• Lights- positioning? use less light by sensor switches? filtering less harsh on eyes inside? less light pollution outside?

I’ve ordered my pump and decided to try working without tubing… I hope that I can use fishing line to let the water drip down to the plants (with ceramic pellets acting like beads on the line). There are some major questions about evaporation and water flow, but I’ll let you all know if it works! I’d also like to make a basic PVC hydroponic system that garuntees some level of success- so if anyone wants to build that together, I’m game. I started posting some things on http://windowfarm.tumblr.com/ and I’ve attached my drawing plans as well.

xCaroline