In my windowfarm I have chosen to use clay pellets. Before putting the pellets in the bottles I washed them to get rid of all the dust, but apparently not thoroughly enough. Dust from the clay have gradually come loose and clogged the system.I don´t know if there are different qualities of clay pellets. But I have bought different brands in different price ranges and there has always been with both dust and small pieces of broken pellets.
Now that I bought new pellets, I have washed and washed and washed to be sure to remove all loose particles.

Lesson learned:
When you think you’ve washed enough, wash some more.

I was just introduced to window farming yesterday and I am so excited to start my own… It’s also wonderful to know that people around the world are also interested and taking part.

I have a question relating to the soil and pots that people are using in their window farms: what is the benefit of using clay pellets opposed to regular gardening soil? What exactly is a “net cup” (mentioned in the instructions)? Is this a mesh sort of pot that the plants sit in?

What have other people used and how has it affected your crops/plants?

Looking forward to hearing from people and experimenting myself/reporting my findings.

Thanks

EmB

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.

-Britta

The Mystery Planter, then. The upper part of a water bottle a new substrate to test (crushed-clay-pebbles-with-fancy-name) , four or five different seeds, and a wick.

Which, as it turns out, is made of the wrong material: a piece of coco mat whose ability to wick up water is zip. Lesson learned, felt’s next.

But at least the larger seeds I put in don’t seem to mind much, and because my WF is hanging in a brighter and warmer spot now, evaporation – something the coco is capable of supporting apparently – currently supplies enough moisture to keep them going. It remains to be seen whether their roots will reach far enough before they run out of puff.

Derek Stobbard wrote me an email with this idea for nutrients:

“Here’s an idea for natural nutrients: Keep fresh water fish – goldfish, for instance. Once a week empty one fifth, to one third of the water from your fish tank and replace it with new water (preferably water that has sat in a bucket for a day – to get rid of the chlorine). Empty the water you took out of the fish tank into your watering reservoir. This water will be rich in nitrates from your fish’s “waste” which plants love, and if you feed your fish sustainable and organic food, so much the better. As long as you are doing this regularly, your fish water should not smell. Beware of algae, keep your fish tank out of direct sunlight, as algae will consume the nutrients and the oxygen from the water.

If you grow anything other than green leafy plants you may need to add very small amounts of calcium, iron and potassium from time to time (once a month). However, you may get away without it since you use clay pellets as a solid medium in your pots, and this has trace amounts of these necessary elements. Also, depending on the food you give your fish, some of these may already be present in the uneaten food, and will make their way into the water. ”

I love the idea and generally love the idea of aquaponics (fish + plant system). I continue to remain skeptical about incorporating fish into the windowfarm because forcing symbiosis between two different ecosystems is pretty complicated stuff and the balances can get out of wack really quickly meaning you could end up with a bunch of dead plants and fish really fast.

I like that he proposes simply using the fish water as a nutrient source and moving that water to the windowfarm after a simple filtration process. Anyone want to try it out? We would need a control group as well. Build two airlift systems- one using fish waste and the other using the recommended (Sugar Peak Organic Hydroponic Vegetative Nutrients) commercial nutrients? That would be rad, guys.

Remember everyone, creating nutrients is a pretty sophisticated biochemistry application so you gotta be ready to be super experimental. You probably will lose a lot of plants along the way. If you just want beautiful veggies you can eat asap, start by experimenting with existing hydroponic nutrients and only make slight modifications to start with.

Images

See some initial research here