Why Hydroponics?

Hydroponics is often defined as “the cultivation of plants in water.” Hydroponics is however a technique for growing plants without using soil. Utilizing this  technology, the roots absorb a balanced nutrient solution dissolved in water that meets all the  plants developmental requirements.

Research has determined that many different aggregates or media can support plant growth,  therefore, the definition of hydroponics has been broadened to: “the cultivation of plants without soil.”

ADVANTAGES OF HYDROPONICS

As demonstrated by through research activities, including field trials, hydroponics is a far more economical and profitable technique than traditional agricultural cultivation.

Some of the advantages noted:

1.     The possibility of obtaining more products in less time than using traditional agriculture:

2.     The possibility of growing plants more densely

3.     Possibility of growing the same plant species repeatedly because there is no soil depletion

4.     Plants have a balanced supply of air water and nutrients

5.     More product/surface unit is obtained

6.     Cleaner and fresher products can be reaped

7.     Production can be timed more effectively to satisfy market demand

8.     Healthier products can be produced

9.     Products are more resistant to diseases

10.                        Natural or Biological control can be employed

11.                        Soil borne pests (fungi) and diseases can be eliminated

12.                        Troublesome weeds and stray seedlings which the result in the need for herbicides  use and increase labour cost, canalso be eliminated.

13.                        Reduction of health risks associated with pest management and soil care.

14.                        Reduced turnaround time between planting as no soil preparation is required

15.                        Stable and significantly increased yields and shorter crop maturation cycle

16.                        Can be utilized by families with small or no yard space

17.                        When water is used as the substrate:

a.     no soil is needed

b.     the water stays in the system and can be reused - thus, lower water costs

c.      It is possible to control the nutrition levels in their entirety - thus, lower nutrition costs

d.     No nutrition pollution is released into the environment because of the controlled system

18.                        Pests and disease are easier to get rid of because of container mobility

DISADVANTAGES OF HYDROPONICS

1.     Commercial Scale requires technical knowledge as well as a good grasp of the principles.

2.     On a commercial scale the initial investment is relatively high.

3.     Great care and attention to detail is required, particularly in the preparation of formulas and plant health control.

4.     A constant supply of water is required

Crop (No. of harvests a year using hydroponics)	Yield using soil (tons per hectare at harvest time)	Yield using hydroponics (tons per hectare at harvest time)
Lettuce (10)	52	300-330
Tomato (2)	80-100	350-400
Cucumber (3)	10-30	700-800
Carrot (1)	15-20	55-75
Potato(1)	20-40	120
Peppers(3)	20-30	85-105
Cabbage(3)	20-40	180-190

PRODUCTION SYSTEM

Hydroponics can be classified as:

-  Open system; or

-  Closed system

OPEN SYSTEM:

In the open system of hydroponics, the nutrient solution is mixed and applied to the plant as  required, instead of being re-cycled. Examples of some open system are:

-  growing beds

-  columns made out of tubular plastics or vertical and horizontal PVC pipes

-  individual containers e.g. pots, plastic sacks and old tires

CLOSED SYSTEM:

In this system the nutrient solution is circulated continuously, providing the nutrients that the  plant requires. Examples of closed systems include:

-  Floating roots

-  Nutrient Film Technique (NFT)

-  PVC or bamboo channels

-  Plastic or polystyrene pots set up in columns

MAJOR REQUIREMENTS THAT A HYDROPONICS SYSTEM MUST SATISFY

-  Provide roots with a fresh, balanced supply of water and nutrients

-  Maintain a high level of gas exchange between nutrient solution and roots

-  Protect against root dehydration and immediate crop failure in the event of a pump failure or power outage.

LOCATING A HYDROPONIC GARDEN

1.     Avoid heavily shaded, windy and extremely sunny places.

2.     Keep the garden protected from domestic animals and pets.

3.     The planting space must receive a minimum of six hours sunlight.

4.     Must be close to a source of water and the place where the nutrients are kept.

5.     It must be kept far from contaminated water.

6.     It must be kept far from trees and other plants that are affected by pests and diseases.

SIZE OF THE HYYDRONNICS GARDEN

1.     Space is not an important factor in hydroponic gardening.

2.     A   garden   can   be   set   up   in   spaces   as   small   as   1m².  Most   of   hydroponic   gardens   are   any   size between 10 to 20m², but some families are able to keep gardens as big as 200m².

3.     Within as small space, one may produce enough vegetables that will be nourishing and free of pollutants.