Hydroponics is a technique used for growing plants in nutrient solutions with or without an artificial medium
A major problems in growing crops in soil
- Presence of disease causing organisms
- Unsuitable soil reactions
- Compaction of soil
- Poor drainage
- Soil erosion
- Continuous cultivation cause soil infertility
Advantages of Hydroponic cultivation
- Maximum crop yield
- Crop production where no suitable soil exists
- Efficient use of water and fertilizers
- Minimal use of land area
- Suitability for mechanization and disease control
Disadvantages of Hydroponic cultivation
- Highly capital intensive
- Skills and knowledge needed to operate/manage the system.
- Due to the high cost only high valued crops are feasible
- Diseases could spread faster
- Cannot use for all the plant varieties
Setting up a Hydroponic system Requirements
- Growing Chamber – protect the roots from light, heats and pests
- Reservoir – holds the nutrient solution mixed with water
- The nutrient solution – contains all macro and micro nutrients (Alberts solution )
- Submersible Pump – pump the water from the reservoir to the growing chamber.
- Air Pump – supply air and oxygen to the water and roots keep the water oxygenated.
- Grow Lights – optional
- Growing medium and net pots – friable, moderately fertile, well drained, sufficient water holding capacity, good aeration and free of the pests and diseases (clean with 10% sodium hypochlorite).
Methods and timing of nutrient solution delivery
- Drip irrigation – intermittent delivery to the base of the plant, frequency and rate of the flow are adjusted to the stage of the plant and the environmental conditions usually the area around the dipper is saturated initially then drains away drawing air into medium.
- Ebb and flow nutrient solution system – nutrient solution is pumped into the growing medium , flooding it with solution for a short period, then return back to the reservoir.
- Standing aerated system – Roots are suspended continuously in a aerated nutrient solution
- Nutrient Film Technique – nutrient solution is passed through growing chamber as a thin film
- Aeroponics system – nutrient solution is applied as a fine mist on the roots. the finer the mist, the better the plants performance.
Types of Hydroponic systems
- Non Aggregate systems (liquid hydroponics) – Nutrient solution without the supporting medium
- Aggregate systems (Solid media culture) – Nutrient solution with supporting medium
Non Aggregate systems
- Nutrient film technique
- Deep flow technique – The bottom of the net pot touches the nutrient solution
- Ebb and Flow technique – The plants are grown in pots (net pots) and then placed in such way that the lower 2-3cm of the pot is dipped into the nutrient solution.
- Root dipping technique – young root system must be in the air and the rest is submerged in the solution
- Floating technique – small pots are fixed to a Styrofoam sheet or any other light plate and allowed to float on the nutrient solution filled in the container and solution is artificially aerated.
- Capillary action technique – Aeration is very important in this technique. Therefore, old coir dust mixed with sand or gravel can be used.
Aggregate systems
- Hanging bag technique – white (inside black), UV resistant, polythene bags filled with old, sterilized coir-dust are used, capillary tube leading from main supply line to each plant,
- Grow bag technique – troughs lined with thick water proof material, The nutrient solution and water are supplied through a drip irrigation system
References
- https://www.supragarden.com/SHOP/Air-Pumps
- N. (2014, June 14). 7 Different Types Of Hydroponic Systems – NoSoilSolutions. NoSoilSolutions. https://www.nosoilsolutions.com/6-different-types-hydroponic-systems/