Growing crops hydroponically is an environmentally friendly way to farm for several reasons. First it increases the amount of nutrients picked up by the plant, second it almost eliminates pests found in soil and soil related diseases. Thirdly, hydroponically grown crops tend to yield more produce than their planted cousins. That being said, there are several types of hydroponic systems that can be suitable for the home grower as well as for large-scale commercial use.
Several popular systems are the Ebb and Flow, Aeroponic, NFT or Nutrient Film Technique, Continuous Drip, Rockwool Based and Europonic Systems. Since hydroponic systems can come in different sizes you can scale any one of these systems to fit your budget.
NFT or Nutrient Film Technique
Let’s start with the NFT, Nutrient Film Technique, which is a popular system. In this system the plants are suspended in troughs and the nutrient solution is constantly running through the troughs. The nutrient solution is held in a reservoir equipped with a submersible pump. Solution is always being re-circulated to the beginning of the trough system. It trickles past the roots before finally falling back into the reservoir to start the process over. Sometimes rain gutters are used as troughs and they can be fixed to the side of a wall in such a way that the water starts at the topmost gutter which is placed on downward angle so the water falls into the next gutter. And so on until it ends up back in the reservoir to start over. Commercial systems would have larger troughs to facilitate more flow over the roots.
Aeroponics is the next type of system. In this system a plants roots hanging in such a way that they are exposed to the air. In this system the plants grow without a medium in a kind of misty environment where the roots are sprayed with nutrient solution. The stems of the plants are supported by many kinds of materials such as foam, neoprene, or web pots. A trellis can be used to support the plant once it starts to bear fruit. Leafy green vegetables and herbs do very well in an aeroponic system. These systems can also be used for propagating plants after the seedlings have germinated.
The Europonic System incorporates the use of rockwool or mineral wool, as it is sometimes called. This material is made from molten rock at about 1,600 degrees Celsius that is spun much like the way cotton candy is made and it is similar to insulation. It is used because of it’s ability to accommodate intricate root systems. Rockwool is able to hold large amounts of air and water which are very important to a healthy and productive plant.
In a Europonic System, which gets it’s name from the commercial systems used in Europe, trays have plants growing in the rockwool which have hoses that deliver solution to each individual plant. The solution trickles down to the roots until it makes it’s way back to the reservoir where it is constantly recirculated. Plants such as tomatoes, cucumbers, large flowering plants and peppers are good candidates for the Europonic System.
Continuous Drip Systems
Next, the continuous drip system incorporates a single plant in a pot with a small reservoir under it to recover nutrient solution. Usually a drip ring is used to supply a constant stream of solution to the plant. Holes in the bucket or pot allow the solution to be caught in the reservior and reused. This is the easiest system to set up and great for a little experimentation. Commercially it is not used because it is not feasible in large-scale production.
Ebb and Flow Systems
Lastly, Ebb and Flow systems are built on the idea that grow out trays are repeatedly flooded then allowed to drain. Crops like lettuce, peppers, tomatoes and flowering plants do very well in an ebb and flow system.