Hydroponic

Hydroponic culture

Hydroponics is a method of growing plants using mineral nutrient solutions, in water, without soil. Terrestrial plants may be grown with their roots in the mineral nutrient solution only or in an inert medium, such as perlite, gravel, mineral wool, or coconut husk.

Soilless culture

Gericke originally defined hydroponics as crop growth in mineral nutrient solutions,onics is a subset of soilless culture. Many types of soilless culture do not use the mineral nutrient solutions required for hydroponics.Billions of container plants are produced annually, including fruit, shade, and ornamental trees, shrubs, forest seedlings, vegetable seedlings, bedding plants, herbaceous perennials, and vines.

Most container plants are produced in soilless media, representing soilless culture. However, most are not hydroponics because the soilless medium often provides some of the mineral nutrients via slow release fertilizers, cation exchange, and decomposition of the organic medium itself.

Techniques:

Ø  The three main types of solution cultures are

Ø  Static solution culture,

Ø  Continuous-flow solution culture

Ø  Aeroponics.

Static solution culture:

Ø  In static solution culture, plants are grown in containers of nutrient solution, such as glass Mason jars (typically, in-home applications), plastic buckets, tubs, or tanks.

Continuous-flow solution culture:

Ø  In continuous-flow solution culture, the nutrient solution constantly flows past the roots.

Ø  It is much easier to automate than the static solution culture because sampling and adjustments to the temperature and nutrient concentrations can be made in a large storage tank that has potential to serve thousands of plants.

Aeroponics:

Ø  Aeroponics is a system wherein roots are continuously or discontinuously kept in an environment saturated with fine drops (a mist or aerosol) of nutrient solution.

Deep water culture

Ø  The hydroponic method of plant production by means of suspending the plant roots in a solution of nutrient-rich, oxygenated water.

Ø  Traditional methods favor the use of plastic buckets and large containers with the plant contained in a net pot suspended from the centre of the lid and the roots suspended in the nutrient solution.

Ø   The solution is oxygen saturated from an air pump combined with porous stones.

Ø   With this method, the plants grow much faster because of the high amount of oxygen that the roots receive.

Nutrient solutions:

Ø  Plant nutrients used in hydroponics are dissolved in the water and are mostly in inorganic and ionic form.

Ø  Primary among the dissolved cations (positively charged ions) are Ca2+ (calcium), Mg2+ (magnesium), and K+ (potassium);

Ø   the major nutrient anions in nutrient solutions are NO−
3 (nitrate), SO2−
4   (sulfate), and H2PO−
4 (dihydrogen phosphate).