I want to start a DWC hydroponics system on my balcony but have concerns about the safety of the plant containers.
The first idea was to use plastic sauce buckets from the local snackbar. They’re a waste product and you can easily get a large stack of 10L buckets for free just by asking. They’re initially food safe material and all you have to do is wash out the sauce residue.
The problem is though that this food safety won’t last long in sunlight. The plastic will inevitably break down and release contaminants into the plant water and therefore will also end up in whatever vegetables that are growing in it.
I have considered getting other materials, such as glass vases or perhaps stoneware. Both are heavy and anything large enough is also quite expensive. Weight is a consideration as well on a balcony.
Another option would be to cover the plastic buckets with some plate material with a few holes in it for the plants.
Am I overthinking this? I’m trying to avoid plastic whenever possible but with the right precautions it shouldn’t be that bad.
Can you get some clay?
Lining the inside of these plastic buckets with impermeable clay should provide a barrier that prevents any bad plastic chemicals from getting through to the plant inside. Being supported by plastic means the clay can be thinner and doesn’t need to be fired to be stable, so it’s cheaper and easier than making your own clay pots.
(Though if you have a good natural source of clay nearby that you won’t get in trouble for taking from, making your own earthenware pots from scratch could be very rewarding. Look for the “Primitive Technology” channel on youtube for some examples of how simple that can actually be to do.)
I’ve thought about this. It’s likely going to be very messy and clay will never be waterproof unless you fire it or use some chemicals which are worse than the plastic.
Clay is porous even when fired
Wait, I just randomly had the perfect idea for your situation!
Line the inside of your plastic pots with aluminum foil!
Aluminum foil is relatively affordable and easy to get, and it will provide a long-lasting, food safe, and completely impermeable barrier between the plastic and the plant inside. If possible (given the size of your pots), you’d want to apply it all in one piece, but if the pots are too big for one continuous piece of aluminum foil to cover, you can join two or more sheets of aluminum foil by folding the edges together tightly.
Hmm, aluminium foil should be on the outside, not inside. It will slowly dissolve in (acidic) hydroponic nutrient solutions. I wonder how bad that is. I’ve tried aluminium foil before and it sound simple but actually becomes quite messy.
As a bonus, it scares pigeons away as well. This might be a good way to do it.