Windowfarm, Version 2.0

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So, remember the Windowfarm I started last year?
Well, it had some issues. Keeping the water flowing was just not happening without a pump, and I don’t want to have to listen to a pump going every so often … I hate mechanical noises.
So I did some more reading, and found out more about passive hydroculture – basically, growing plants in liquid. Now, if you just put plants in water the roots will drown, they do need air. This is where hydroton comes in: those expanded clay pellets hold water and make it available to the plants, but they also hold air, so the roots don’t get waterlogged. Basically, you put a bare-rooted plant in a dish of hydroton pellets, water it (with liquid fertilizer so it has nutrients to grow), and that’s it. No flushing, pumping, or anything.
I’ve got a couple of house plants that have successfully survived in hydroculture for over six months now, so I figured maybe I’ve got the hang of this.
I started my seedlings in rockwool cubes: handy little bricks of finely packed threads of something that works like hydroton but is smaller. Soak them, put the seed in the hole, label the cube (a cut up yogourt container makes nice little tabs that slide easily between the rock wool and the plastic wrapper for the cube) and set the cubes in a turkey roaster with a plastic domed lid. The turkey roaster sits on top of my gas stove, where the heat from the pilot lights keeps the whole thing nice and warm, encouraging the seedlings to sprout. The lid keeps the moisture in, and I just pour a bit of water in the bottom of the pan every so often to make sure the cubes don’t dry out.
When the seeds sprout, I take the cube over to the windowfarm, which is still mounted in the south facing window. For those just joining in, the windowfarm consists of plastic eavestroughing with the ends capped, suspended from that metal shelf support stuff with the holes in it (which you would normally hook a little shelf arm into, but for this purpose, a loop of metal from a set of old window blinds is wired through the holes, it’s nice and strong and holds the weight of the full trough just fine). The rockwool cube with it’s new seedling gets nestled into the hydroton that fills the trough, and the trough is then watered generously.

I do have drain holes in the ends of my troughs (from the previous attempt at an ebb and flow kind of set up) but I just hook the tubing up over the edge and clip it in place so that the water doesn’t drain out.
The window faces directly south and gets a lot of bright light. I’ve been keeping the drapes closed, which traps the plants between the glass and the curtains, and the light bouncing off the light beige curtains seems to be helping the plants to stand mostly upright, rather than leaning drunkenly towards the glass like they usually do. It would be ideal to have a little fan blowing on these seedlings to help them get stronger, but I haven’t got anything suitable (I’m keeping an eye out for a solar powered fan that might work in this application).

As you can see, the tomato plants are quite happy in this location. Today they got their first drink of hydroponic-nutrient-enhanced water … up until now they’ve just been watered with plain, out of the tap stuff, but they are big enough I figure they would benefit from some extra nutrition.
So far, so good. We’ll see how they hold up as they get bigger … I am going to attempt a few pepper plants, I think – they won’t make it outside in our climate (or not very well anyway), ‘cause they  like more heat than we get, so I think perhaps the window will be warm enough to get some good pepper growth. Worth a shot, anyway!