Hydroponics without using pumps: Is it possible?
The short answer is: Yes!
A few years ago, I was curious if hydroponics was even possible in a situation where there wouldn’t be any electricity. I know, if you didn’t have electricity, you could set up a small solar panel system and have a pump run off the electricity made by the sun, totally off the grid. Yes, that would be “off the grid,” but what if there was a circumstance arose where you didn’t have any solar panels, batteries, or even a pump to pump the water? Then, you would be left with either planting in the ground and hoping that you have enough nutrients in the soil to produce food, or simply do without. If you have a family, doing without is not an option.
Everyone doesn’t have fertile, well watered soil to grow food in abundance. So, hydroponics seems like a perfect choice to grow food in barren, dry places or in a small setting without dirt like a patio or balcony. Mind you, this method can be painstakingly difficult to get the nutrients and PH balance right amongst many other factors. The trade off for considerably larger fruits and vegetables while using 90% less water against this aggravation, in my opinion, seemed like it was worth a try. Hydroponics gives you control of every aspect of the growing conditions, making each plant certifiable for an organic label or just grow like crazy. Personally, I did both and learned a lot along the way.
I found this article about B. A. Kratky’s Suspended Pot, Non-Circulating Hydroponic Method. It describes how to grow lettuce or other leafy vegetables easily without using any circulating pumps. Essentially, after you build the system and get the plants started, the bottom roots of the plant follow the water level down as the plants grow allowing the tops of the roots to change by becoming thicker and more branched so that they may absorb more oxygen. The plants do this naturally so you don’t have to do anything but sit back and watch your plants grow.
While shopping one day, I came across a product called AeroGarden. It was a full hydroponic kit that can sit on your counter top, growing fresh herbs to use as you needed them. It seemed like a wonderful product, but a little too pricey for me.
I did purchase their seed pod kits to see if I I could use them for something. Turned out, they fit snuggly into the mouth of any gallon milk jug or perfectly in the mouth of a one gallon orange juice bottle. This seemed like a great way to reuse something that was getting thrown out or recycled. I couldn’t use just any milk or orange juice bottle, it had to be opaque to block as much light as possible. This was a fitting container as it seemed like they were every where, and with as much milk and juice as my family drink, easy to come by. Having an opaque container helps to cut down on the algae growth in the nutrient rich water, and stealing those nutrients from your plants. The AeroGarden seed pod kits also comes with a small bottle of water soluble hydroponic nutrients that came in handy. I followed the instructions for the nutrient mixture, which was also easy since the instructions were for a mixture by the gallon. I filled the bottle up to where the bottom of the seed pot dipped down into the water and wicked the water up to where the seeds were. The next step was the waiting…
So far, I’ve done this three years in a row, with different results.
The first year, I grew only three heads of Romaine leaf lettuce. I followed the AeroGarden directions precisely for two of the jugs and for the last, I used liquid based Miracle-Grow fertilizer. It seemed that the AeroGarden fertilizer had better nutrients and grew better plants. After a little over a month, I harvested one of the AeroGarden fertilizer lettuce and the Miracle-Grow fertilizer lettuce and used them to make a large salad. It was delicious! The last lettuce I left to grow as long as it could, refilling the reservoir back up to half way with more nutrient water when it would get low. It went for more than three months like this. I only picked the outside leaves as I needed them, letting the plant get quite large and flower. I then harvested as many seeds as I could before the wind would blow them away.
The second year, I decided to try something a little different with the lettuce. I saw where you could grow plants with just dirty fish water, they call this Aquaponics. I used that idea and used the water that I was normally pouring down the drain, when changing out the fish tank water, to fill up the containers. I still added the nutrients with the fish water just in case it wasn’t enough. I also let two lettuce plants grow in a single container thinking I could double production. This was a mistake since the two plants were fighting for space and crowding each other out, ultimately stunting their growth. The other lettuce seemed to grow like crazy! It seemed that the fish water was a success. Things were great until a wind storm came by and blew the almost empty milk jugs (that I needed to refill) across the yard breaking the stalks and killing the lettuce. I was devastated, at least until we ate salad for supper that night.
The third year, I thought I would venture out of the realm of just lettuce and try cherry tomatoes. Once again I should have learned from the previous year about only letting one grow per container. I let two tomatoes grow together and they crowed each other out and got so heavy with cherry tomatoes that it broke the stems on both plants from leaning and trying to carry the weight. The tomato plants grew well since they were small bushy plants made for the AeroGarden. Of course I had to refill the containers more often since tomatoes consume more water than lettuce. Normally, this wouldn’t have been a problem until I had to pull some extra time at work and totally forgot about my little garden. The plants dried out and died with little shriveled tomatoes still hanging on the branches. It was quite depressing. Luckily, the growing season wasn’t over and I could start over. Even better, when it starts getting colder, I can bring in the jugs through the night to avoid the frost and then take them back out to get the warm sun during the day.
Of course all of this could be done with so many variations. It seems that this technique is simple and very forgivable. I’ve seen in a few videos where they took a five gallon bucket or a wide Rubbermaid container and cut more holes in the lid creating the exact same idea as I’ve described here but growing more heads of lettuce in the same container without the crowding issues. Also, it seemed more stable and less likely to be top heavy.
If you do decide to try this on your back porch (like I did) or on a balcony, good luck! I think you will have a fun learning experience as I did. If you decide to take this idea further and try to make it into a commercial size growing medium, I would suggest that you do more research before jumping into this method. It can be done on a large scale, but the bigger the undertaking, the more the problems and headaches that follow.