Hydroponic Gardening in Mason Jars
Here in the tundra, anything green gets shipped in from California during the winter months (e.g. half the year) on diesel trucks in non-recyclable plastic bags and is like death to the zero waste soul. I enjoy a good salad and have been working on a system that supports a salad eating habit without the associated grocery store waste.
Above is my salad photo shoot being hijacked by my toddler.
A core issue of zero waste is that a huge percentage of the waste we produce is related to eating – whether it’s the tractors harvesting or the trucks bringing us food, or the packaging we’re throwing away, or the cars we’re using to drive to the grocery store. You can’t get much closer to zero waste than growing food yourself.
In our daily lives some foods are worse than others – for example salad and berries, which come in a lot of packaging and spoil quickly. So greens were my first priority since they are easy to grow in a small space and have minimal requirements for life.
Click and Grow
While I was reading about cold frame gardening and regular outdoor gardening, I was asked to review this product:
Click & Grow is a really interesting but expensive concept. It’s completely self contained so that you have to do nothing except add water every few weeks. The seeds are pre-planted in a proprietary spongelike substance that wicks moisture up perfectly and the grow light has a built in 16 hour timer, so you just plug it in, fill it with water and let it grow.
The problem with it is that it’s really not big enough. Basil is a large plant and these plants hit the light and started getting tip burn. Because I don’t know anything, I put them outside. I had no idea that you had to harden off seedlings and so they died.
Of course you can buy capsule refills but I’m not sure I agree with that amount of plastic on a moral level so I tried it with regular soil, expecting it not to work. It didn’t. My guess is that the soil absorbed too much water and drowned the plants’ root system.
Growing food in soil indoors doesn’t work
Hooked on the concept, I started researching indoor growing methods. I learned that growing food in soil inside is a bad plan because soil is alive and the bad bacteria overpowers the good bacteria and the plant dies a sad and pathetic death (also known as damping off). I should also note here that growing plants for decoration and growing plants for food are different. Keeping something alive is easier, getting something to grow quickly so you can eat it is something different entirely.
Enter hydroponics. The standard version is circulating hydroponics which is supposed to have a ridiculous number of benefits including plants growing at twice their normal rate because they don’t have to work as hard to extract nutrients and water from the soil. This was intriguing to me, and also to marijuna growers everywhere.
There are a number of different methods for circulation. Juice Plus even has an elegant hydroponic tower, which costs around $600. If you want one let me know and I can put you in touch with a Juice Plus person. For the purposes of this blog I assumed a good number of people would not be looking to shell out that much money. I also was concerned about having this system in our house because of our ongoing slew of toddlers.
So I read some do it yourself posts and had all kinds of components in my Amazon cart ready to buy when I read a comment on a blog that said something to the effect of “why bother unless you want a higher electricity bill” and mentioned the Kratkey method.
Essentially the idea is that you start a plant in a closed container (like a mason jar) and as the water level lowers the upper roots are in a humid environment and able to take in oxygen from the air, while the lower roots are in the water and able to continue to use water in the jar. It is essentially a no maintenance approach, but supposedly takes about two weeks longer to grow than circulating methods.
(Curious what the catch is? This post talks about common problems with hydroponic methods.)
Plant requirements for non-circulating hydroponics
What I like about this approach is that anyone can do it. It’s relatively easy to set up and you can do it at on a small scale. The requirements are as follows:
- A light that can be adjusted to be 4 to 6″ above the plant in the “just right” zone (e.g. a gooseneck lamp)
- A full spectrum light bulb. The system I used included a grow bulb but full spectrum light bulbs can be purchased separately and put in a regular lamp.
- Nutrient solution: FloraGrow is the standard – I realized later that FloraMicro is high in nitrogen, which you want for green leafy growth so it’s good to add both)
- Net baskets, or a way to suspend the plants so they don’t drown.
- Seeds: Johnny’s Selected Seeds was recommended to me and I’ve been really happy with them.
- Some kind of growing medium for the seeds, such as Coconut Coir Grow Discs (more on this below)
- 1 quart regular width mason jars(if you use this link, be sure to change the mouth type to regular instead of wide.
1. The light must be 4 to 6″ from the plant. The intensity of light falls off very quickly and if the light is too far away it’s not only exponentially dimmer, but makes the plants become leggy (which makes them fall over when they get biggger) as they grow toward it. So you need to be able to raise the light as the plants grow and lower it for new seedlings. You can use a gooseneck lamp with a grow lightbulb, or something like this:
I really like this light, but I think it looks a little too institutional in my kitchen.
It went well enough that we decided to get a proper light fixture. I discovered this and splurged a little.
I can raise and lower the lights and I have them on a timer so I don’t have to do much of anything other than pick and eat. To me it still looks a little cluttered but I haven’t had time to deal with it. Also, each light bulb can grow about 9 plants, giving me a total of 27 jars. I’d hoped for more since we can harvest 1-2 servings of salad every three to four days. If you had a space where you could get really practical then I’d imagine you could get some higher powered lights and grow a lot more plants.
2. The lightbulb must deliver a full spectrum of light (e.g. a grow light instead of a regular light bulb). It turns out that the sun is better than you thought providing all kinds of wavelengths and such for food to grow. For that reason, you need a full spectrum bulb or your food won’t grow.
3. The plant needs nutrients in the water. We used 1 teaspoon per mason jar of both FloraGrow and FloraMicro. We started with just FloraGrow, but then I realized that lettuce is a high nitrogen consumer and FloraMicro is high in nitrogen.
I also bought a PH test kit but the water is neutral and I really haven’t had an issue with it. I suspect this would be more of an issue in a circulating system.
4. The plants need to be suspended so they don’t drown. Plant roots need oxygen.
It turns out that these plant baskets are the perfect size for a narrow mouth mason jar with the screw thing screwed on. You could also use yogurt cups, but I’m a visual type of person and that wouldn’t do it for me.
5. You need seeds – not much more to add here!
6. Seed starting pellets. I actually had a really hard time finding a growing medium I was happy with, so be sure to bookmark this one. Initially I used peat pellets and did a little research and learned that peat takes thousands of years to form and therefore is not ecologically sound. Some people argue this point, but it’s really not necessary so I can skip it. I then came across Jiffy pellets but apparently they use polymers (plastic, which does not decompose). After that I looked into rock wool, and there are problems associated with that as well. So overall it seemed like the best option was Coco Coir Grow Discs which are made from coconut coir which is a byproduct of coconut production that would otherwise be discarded. But when I ordered them they literally disintegrated. So if you have any recommendations, I’m open to them! For now, I’m using the jiffy pellets but would love to switch.
This may seem obvious but is worth mentioning – you can’t use soil because it falls apart in the water and the seeds do need something to hang onto when they are very small.
7. And you need jars, which can pretty much be purchased anywhere.
I’d love to hear your thoughts and comments below!