Tabenas Goes Green

The Secret World of Aeroponics

by Shane Caraway

Aeroponics is relatively new form hydroponics. The plants are placed in a basket or netted pot and suspended over a water reservoir while the roots are sprayed with a water/nutrient solution. This allows the roots to get the maximum amount of oxygen. You might say, "I thought plants liked Carbon Dioxide (CO2) or how can the roots get oxygen when they're underground?" It's true plants love CO2, but the roots are the opposite. Roots need oxygen. Soil, for healthy plants, needs a certain amount of sand in it (among other things.) Sand allows the water to drain from the soil and prevent "root rot." If you over-water your plants, you're suffocating the roots. The same goes for standard hydroponic systems. Most of them have some sort of system to both oxygenate (air stone) and exchange (pump) the water around the roots.

The Aerospring system I built is based around the design I found in a book called "How To Hydroponics" 4th Edition by Keith Roberto. I took Robertos design and modified it in a few ways. This, video, is similar to his Aerospring System.

My aerospring differences are:
-I extended the PVC pipe that you attach the sprayers to and drilled holes in the sides of the tub for it to fit through. It should be a snug fit to prevent leaks without using any sealant or rubber grommet.
-I added a second tub and extended the PVC through it also. (The pump I used could easily support a third tub)
-I left the sprayers off. When they clog up, it's difficult to clean them. The water hits the underside of the lid and sprays the roots. Not as effective, but adequate.
-The drain from the second tub back to the pump needs to be at least 3/4" for proper drainage.
-One end of the PVC should have a removable cap to allow for emptying the system using the pump, when necessary.
-I left out the water level sight tube. It's easy to look down into the system when necessary.
-I keep the water level just above the pump, not full. Multiple containers require a large amount of water if full.

Shane's Aeroponic garden

The main benefit of growing the plants aeroponically is a rapid growth rate -up to 10 times that of plants grown in regular soil. The extra oxygen provided to the roots is an added benefit over standard hydroponics. Less water is necessary compared to a soil garden also. I personally like the sound of the system running because it reminds me of rain or a waterfall, soothing. The worst drawback is if the roots are dry for more than 10-15 minutes you risk damaging your plants. Also a possible power or pump failure could ruin your garden. Once the roots reach the water in the basin, you shouldn't have to worry about it.

- Shane Caraway

shanecaraw@yahoo.com