Building my Hydroponic Garden

I decided one day that I’d like to go ahead and throw together a little bookshelf hydroponic garden in my guestroom. I’m more than a little left-brained, so I felt confident that I could build a solid system, and figured, Hey, what’s a little PVC? Well, as I went through the processes of designing the system and learning about hydroponics and plant propagation, I realized that I had stepped into a slightly deeper pool than I’d originally realized. I wanted this system to do well – not only as a hobby micro-farm but as a food source (albeit a minimalist one). In order to do it well, I quickly realized that my vision of a 12-dollar fluorescent shop light fixture and a little tub of water with some fertilizer in it were not going to cut the mustard. This little journal is as much for my organizational purposes as for anything, but it’s probably worth reading if you fancy building your own hydro system and think that it’s going to be a simple affair. I think it’ll be worth it, in the end, but the process has involved a lot (a lot) of organizing, thinking, planning, sketching, reading, purchasing, building, and patience.

There are many formats for setting up a hydroponic system, the main two categories being passive and active. I decided to build an ebb-and-flow, or flood-and-drain system – an active system wherein the nutrient solution recirculates, and which, with due attention to growing conditions and an intelligent setup by design, wouldn’t require hours a day for maintenance and monitoring. I built my ebb-and-flow system from PVC, with the idea in mind that the containers would be attached to the top of the manifold, so the nutrient solution could enter from the bottom of each, and then drain back out. In addition to providing regular doses of nutrient every time the pump was on, and then regular doses of oxygen every time it turned off, the water will push oxygen-poor air up out of the medium as the containers fill, and pull oxygen-rich air down in as they empty.

Originally I had intended to use 2L soda bottles as containers, with the tops pointing down and screwed into the system, and the bottoms cut off; a setup similar to several I’d seen online. However, in order to glue the bottle caps directly into the pipe, I’d have needed to use 1-inch SDR-26 pipe, which is pretty impossible to find. For that reason (in addition to the fact that cut-off soda bottles would always have been unattractive to me and are generally flimsy), I decided to figure out a design using 1-inch SCH-40 PVC, which is far more widely available. The only thing that remained to figure out was what to use as containers. I toyed briefly with the idea of using regular terracotta pots, but I was admittedly nervous that with constant exposure to water, they’d deteriorate and eventually disintegrate. Plastic seemed to be the way to go (and I’m not a plastics fan, but once you’ve built a manifold of PVC, why fight it?). After much completely fruitless shopping around at hardwares, home superstores, and even The Container Store, I ended up at my local 99-cent (“and up”) store, where I found some food-storage containers that fit the bill exactly, for $1.29 apiece. I was about to toss the lids into the recycling bin, but then I realized two additional purposes they could serve. First, since they’re somewhat translucent, I can fit them atop the containers when I’ve planted tender seedlings. Second, and perhaps more excitingly, I could conceivably convert this hydroponic system to an aeroponic system, with a little additional engineering; essentially by removing the medium, drilling large holes in the lids to seat net pots, changing out the water pump for an air pump, and filling the solution tank with nutrient-laden fog instead of liquid solution. Just a thought.

On my next post, I’ll go into how I built this system. Hope you enjoy!