Hydroponics: The Future of Farming?
What is Hydroponics
The act of Growing plants without soil. Word Hydroponic is derived from Latin, meaning working water.
Basically, in hydroponics plants are kept suspended in a medium, other than soil and nutrients are supplied to them with the water.
Why is it so effective
If you give plants exactly what it needs, when it needs it, in the amount that it needs, the plant will be as healthy as genetically possible. In soil, it is more difficult.
Every nutrient is delivered to roots in a pH adjusted solution. Very little effort is needed as the solution is delivered in highly soluble form. Even when everything is made available more effort is needed for the roots to get it from the soil.
The energy expended by the roots in this process is the energy better spent on vegetative growth and fruit and flower production.
Faster, better growth and much greater yields are just some of the many reasons that hydroponics is being adapted around the world for commercial food production as well as a growing number of home hobby gardeners.
Growing Medium
It is the material in which the roots of the plants are growing. This covers a vast variety of substances which include rock wool, perlite, vermiculite, coconut fiber, gravel, sand and many more. The growing medium is an inert substance that does not supply any nutrition to the plants. Everything comes from the solution. The strength and pH of the nutrient solution are easy to adjust so that the plants receive just the right amount of food.
Fertilizer
1. Hydroponic
They are in more refined form with fewer impurities making them more stable and solution for better absorption.
2. Organic
They rely on the synergistic action of bacteria and microbes to break down nutritional substances for easier uptake by the plants.
3. Regular
They come in ready-to-use form. Plants are expected to find proper nutrients from the soil.
Micro-Nutrients (trace elements)
Calcium, magnesium, Sulphur, boron, cobalt, copper, iron, manganese, molybdenum, and zinc.
Deficient in any one of these elements, plants suffer stress, disease become more vulnerable to pests, fungus and bacteria and may have uptake issues with the N-P-K fertilizer they are being fed. Essentially hydroponics fertilizer must have these elements.
pH
The control of pH is extremely important in hydroponics. Plants lose the ability to absorb different nutrients when the pH varies. Ability to test and control the pH in hydroponics is extremely important quickly and easily.
Nutrient Film Technique
It is a recirculating hydroponic system where nutrient solution flows down a set of channels(gullies). The solution is pumped from the holding tank, through irrigators at the top of every sloping channel and he runs off from the bottom of the channels is returned in the tank.
Principle
Plant roots require oxygen in order to respire, that is, to make use of the energy input from photosynthesis. In the process of respiration, plant cells take in oxygen and release carbon dioxide. If roots cannot respire, they will die.
In NFT, it is a fundamental requirement that the plant roots are in a flowing(thin) film of nutrient solution. The impact of the thin film is two-fold. Firstly, some of the roots in the channel will be directly in contact with the air. Secondly, when dissolved oxygen in the water is taken up by the submerged plant roots, this oxygen can be replaced by absorption through the large surface area of the thin water film.
By its nature, the basic principle of NFT is that it is a ‘closed’ circulatory system.
Channel Design
Shape: Shape of the cross-section of the channel should allow the solution flow to have a basically flat profile. A circular tube can be a bad choice.
The width of the channel allows for the size of the root mat of mature crop intended to grow up in the channel. It should be:
100mm (4 inches) for short-term crops (lettuce and herbs)
150mm (6 inches) for long-term crops (strawberries)
200mm (8 inches) for longer term large crops (tomatoes)
Slope: With respect to length, a slope of 1:30 or 1:40 is kept.
Length: Maximum length of trays should not exceed 10–12 m (35 feet max)
Layout: It is a gravity fed system, so the layout is kept slanting
Flow rate: 0.5 liter per minute for 100 mm wide channels growing smaller plants and rest accordingly
Tank size: For smaller plants, 0.5 liter per plant
For large plants at least 2 liters per plant. The tank should be of a dark color
Suitable Plants: Leafy vegetables such as spinach and lettuce, strawberries, cherry tomatoes, pepper, etc.
#Some fertilizers or nutrients do not like oxygen as they will get oxidized in the presence of oxygen. Organic fertilizers contain bacteria which will work differently in presence of oxygen. If sunlight reaches the nutrient solution, algae will generate. Thus, it should be light proof. Only plants should get the light.
