Hydroponic Growing Systems May 12, 2008
There are basically five growing methods that I have considered. Of these five, I am more interested in the Nutrient Film Technique and the Flood/Drain System. I am thinking that the flood/drain system would be best suited to growing tomatoe crops since you can grow the plants in gallon containers supported by expanded clay pellets. For lettuce and other short term crops, the NFT system would work well to grow lettuce 4 inches apart using no soil or grow media. The lettuce only needs to be supported by holes inside a gutter cover. Here’s an explanation of the growing techniques.
Nutrient Film Technique: The nutrient is fed into grow tubes where the roots draw it up. The nutrients mixed into water are pumped into a 5” pvc drain pipe, plastic rain gutters, or other types of water-tight trays. In any of these containers, holes can be drilled into the tops about 2 inches in diameter to place net pots in them to direct the roots into the nutrient mixture and contain the plant.
Drip-Irrigation or Micro-Irrigation: The nutrient solution is delivered to the plants through drip emitters on a timed system. (This would be my second choice other than flood/drain. It seems to be a very efficient system for any type of crop).
Aeroponics / Deep Water Culture: The Plant roots are suspended in highly oxygenated nutrient solution. (For some reason, I don’t like this method. You have to provide constant oxygen to the nutrient solution as it is not recycled as in the other systems. I guess my previous experiences with aquariums gave be a bad taste for maintaining oxygenated water).
Flood & Drain: The plant medium and roots are soaked, and then drained at specific intervals. (My choice for Tomatoe crops).
Passive Planters or Self Watering Wicks: A porous growing medium to support plant roots, the plants in the nutrient solution at all times. The plant takes as much or as little water as they want. (I wouldn’t mind experimenting with a small project of this nature, but I didn’t choose this because buying the porous growing medium on a large scale would be too expensive for me.)
