| | | A Brief Introduction To Methods Of Hydroponic Production | | | | | |
| Hydroponics literally means “water working” however, in practical use, it means growing plants in a nutrient solution without soil. The hydroponic science had proved that soil isn’t required for plant growth but the elements, minerals and nutrients that soil contains are. Soil is a place where the plant roots traditionally live and a base of support for the plant structure. Soil is simply the holder of the nutrients. By eliminating the soil, you eliminate soil borne disease and weeds and gain precise control over the plant’s nutritional diet. In a hydroponic solution, you provide the exact nutrients your plants need in precisely the correct ratios so they can develop stress-free mature faster and, at harvest, are the highest quality possible.
In commercial production, the two primary growing methods are NFT (Nutrient Film Technique) and drip (also known as substrate). There are a number of variations of these methods and also several others including the float system, ebb and flow system, Aeroponics and passive. The biggest difference between the NFT systems and drip systems is the use of a growing medium. In an NFT system, the plant roots are in a channel where a thin film of nutrient solution passes, keeping them moist but not water-logged. In a drip system, the plant roots are in a growing medium such as Perlite or Rockwool and the nutrient solution is dripped onto the medium to keep it moist.
NFT (Nutrient Film Technique)
With the NFT (also known Nutrient Film Technique) technique, the plants are grown in channels (also called gullies) in which the nutrient solution is pumped through. The plant roots are kept moist by the thin film of nutrient solution as it passes by. Ideally, the bottom of the roots is exposed to the nutrient solution while the top are kept moist but not water-logged.
With the development of on-demand dosing equipment, a nutrient reservoir can automatically be adjusted and, with proper aeration and pH adjustment, the system can effortlessly be kept fresh for weeks at a time. Most NFT channels are fed continuously at a rate of approximately 1 liter per minute. Since the plant roots are not in a growing medium, it is crucial that they are kept moist at all times. In most NFT systems, the nutrient solution is mixed in a primary reservoir, cycled through the channels and back to the reservoir.
NFT is ideal for short term crops like lettuce, leafy crops and herbs. In many locations around the world, Larger NFTchannels are used for long term crops such as tomatoes and cucumbers. One great benefit of NFT, especially for leafy crops, is that no washing is necessary since there no growing medium and no soil, and hence the crop is clean. Growers, chefs, grocers and consumers all appreciate this.
Most growers have found flat bottomed channels or gullies provide greater surface area for root development and oxygen uptake, resulting in better, faster plant development. NFT channels are usually set up on waist-high stands that slope slightly to allow the nutrient solution to drain to one end.
Aeroponics
Though Aeroponics is a unique way of growing; it is not a common means of commercial production. Aeroponics is the method of growing where the plant roots are constantly misted with a nutrient solution. Designs include an A-frame with boards on each side, plant plugs set in each side and a mister between the boards spraying the roots. A round, large diameter PVC pipe set vertically with plant plugs all they way around and a mister mounted inside is another way to set up an Aeroponic system.
CONTINUE |
|
|
|
