Step by step construction of my Clay Pots (terracotta) Windowfarm

11:29 pm in Materials and Resources, posts with pitcures!, Projects in Process by Louise from Quebec

Few ! It seems it took me as much time to post this one as to build the real thing. But here it is.  I wanted to make a plastic-free windowfarm that would be appealing to the eye and would blend nicely with our Victorian house, from the inside as well as from the outside. (In French, I like to call it “potager vertical” – vertical vegetable garden).

I wanted a sustainable system, sturdy, easy to handle and that I could easily push away from the window, just like shutters.  At first, I envisioned to pump up the water with an airlift system and maybe l’ll come back to the idea, after all. But having free access to those slow drip tubes made me dream of an electric-free system as well. And how about autonomy : a system that would run by itself or with very few maintenance for up to five or six days ?

Finally, I wanted to nourish my plants with the manure from my earthworm composter.

In the beginnings of my experimentation, my slow-drip system  allowed me 3 to 4 days of autonomy, providing that I readjusted the dripping flow once or twice a day. But then, I discovered that  my plants didn’t need as much water (I have rock wool in my pots as well as clay pellets). So, I’m slowing the flow and closing it off completely during the night. That way, I expect to make my upper reservoirs last for more than seven days before having to refill them (with fresh water and nutrients – the old water will be fed to my ornemental plants, which are planted in soil).

No splashing problems so far : My pots are only 5” to 6” apart, one under the other. Each drop don’t gather enough speed to explode into many droplets and splash everywhere. Also, to direct each drop towards the middle of the pot right under it, I took a Hydroton pellet of just the right size and blocked up the draining hole of the pots with it, making sure that it would protrude outside of (under) the pot. The droplets then gather at the lower part of the clay pellet and are therefore nicely centered before making their dive into the next level of the installation. Eventually, I suspect I will have to introduce a mesh between the clay pellet and the pot’s hole (a short shoe lace should do the thing) to prevent the plants’ foliage from diverting the flow of water outside the pots. We’ll see…

When you click on photos, you have further explanations. After the photos, you’ll find a list of materials and a few more explanations.

The tools I used : hammer, screwdriver, long-nose plier, nail.

Glazed clay pots – Home Depot My window pane is 30” wide and I figured it allowed me 4 columns of pots.

It’s 60” high : so I could put up to 5 pots high (maybe 6 if I manage to put another pot right under the bottom pot of the column and sitting right over the collecting reservoir (I didn’t figure out that one yet)

4” wide : 5,79

5,5” wide : 7,99

(Canadian dollars)

Total 137,80 +tx

Electric Wire (grade 12-1) – Rona 4 lenghts of 160” each (twice the length of the window plus 40” to make loops acting as hooks for the pots).

The thing is rigid and therefore it gives a lot of stability to the whole structure, plus it’s so strong I won’t ever have to worry  about the weight.  It’s not easily deformable, so I can remove any pot in a jiffy without disturbing the rest of the structure, aside from a soft rocking movement.


Total 13,20 +tx

Electric Wire – hook up wire 22 gauge solid 4 lenghts of 160” each plus 12” for each pot.

Total : about 35’

I use this small wire as an anchor to each pot’s collar, to stabilize the pots horizontally, so not much strength is required here.

Recycled material : free
Expanded clay pellets (hydroton)

Rock wool (Rockstone)

pH tester kit

Hydroton : 50L (I have enough for 4 or 5 more windowfarms like this one, but the stores in my area didn’t sell it in smaller quantities !)

1 package of 98 (2”) cubes

I’m trying a mix of 50% rock wool and 50% clay pellets, so my garden could withstand a few days without being watered. I got this idea from this post : November 22, 2010     Window Farms: An experiment in urban agriculture

By Stuart McPherson, Stewardship Co-ordinator, Evergreen Brick Works

Later, I’d like to try compacted coconut fibre instead of rock wool (if I can find some).

1 small bottle of testing solution + 1 empty flask.

Total for these 3 items together :

24,61 +tx

Swivel curtain rods They come in pairs with holding brackets and  8 screws. They extend to over 24” long each.

This model tends to bend a little under the pots weight (it’s designed to support curtains, after all), so I added a swivel bracket to make sure everything is strong enough.

Was given to me for free
Swivel bracket 1 – can hold up to 50 pounds.

Placed just in the middle of the window frame, it supports the extremities of the 2 rods.

4,99 +tx
Black electric tape A few inches is enough, utilized to block the telescopic arms of the curtain rods to the desired length. It came from my husband’s tool box.
Reservoirs Right now, I use different plastic containers and I’ll wait until I can find affordable non-plastic containers to replace them. All recycled material
¼” tubing for enteral feeding with built-in slow drip system (Kangaroo screw cap pump set, from Sherwood Medical – St-Louis / product number 8884-706800) 1 for each column – each is 100” long. This silicone tubing is medical material used to feed someone who cannot swallow any food. As no part of it comes in contact with the patient’s body or body fluids, it’s perfectly safe to reuse it to feed plants. Also, it’s designed to let drip a thick liquid full of nutrient particles, so no clogging problems! The slow drip system is efficient and versatile : you may obtain a steady  stream to flood your pots as well as one drop every 15 seconds, just enough to maintain humidity within the rock wool cube. The only drawback I discovered so far is that you have to either refill your reservoir daily, or adjust the clamp daily, as the gradually changing water level in your reservoir will change the dripping rate as well, eventually bringing it to a stop even when the reservoir is not yet empty. Recycled material

(I know it costs a few dollars for each tubing, but I don’t know if they sell it by unit somewhere)

1 rock as big as a fist for each upper reservoir I use it to anchor the tubing lines at the bottom of the reservoirs. For free,  I just brought back a souvenir from a nice walk in the wilderness !
1 or 2 wooden rods hanging from tea cup hooks. To prevent the bottom pots from slamming into the window pane by accident. Recycled from my old curtain installation
TOTAL COST 180,60$ CA +tx