Advantages and Disadvantages Hydroponics and Soilless Culture

Hydroponics is only one form of soilless culture. It refers to a technique in which plant roots are suspended in either a static, continuously aerated nutrient solution or a continuous flow or mist of nutrient solution.

The growing of plants in an inorganic substance (such as sand, gravel, perlite, rockwool) or in an organic material (such as sphagnum peat moss, pine bark, or coconut fiber) and periodically watered with a nutrient solution should be referred to as soilless culture but not necessarily hydroponic.

Some may argue with these definitions, as the common conception of hydroponics is that plants are grownwithout soil, with 16 of the 19 required essential elements provided by means of a nutrient solution that periodically bathes the roots.

Unfortunately, many workable soilless culture systems are not commercially sound. Most books on hydroponics would lead one to believe that hydroponic/soilless culture methods for plant growing are relatively free of problems since the rooting media and supply of nutrient elements can be controlled.

Experience has shown that hydroponic/soilless growing requires careful attention to details and good growing skills.

Advantages hydroponic system

a. Crops can be grown where no suitable soil exists or where the soil is contaminated with disease.

b. Labor for tilling, cultivating, fumigating, watering, and other traditional practices is largely eliminated.

c. Maximum yields are possible, making the system economically feasible in high-density and expensive land areas.

d. Conservation of water and nutrients is a feature of all systems. This can lead to a reduction in pollution of land and streams because valuable chemicals need not be lost.

e. Soilborne plant diseases are more readily eradicated in closed systems, which can be totally flooded with an eradicant.

f. More complete control of the environment is generally a feature of the system (i.e., root environment, timely nutrient feeding or irrigation), and in greenhouse-type operations, the light, temperature, humidity, and composition of the air can be manipulated.

g. Water carrying high soluble salts may be used if done with extreme care. If the soluble salt concentrations in the water supply are over 500 ppm, an open system of hydroponics may be used if care is given to frequent leaching of the growing medium to reduce the salt accumulations.

h. The amateur horticulturist can adapt a hydroponic system to home and patio-type gardens, even in high-rise buildings. A hydroponic system can be clean, lightweight, and mechanized.

Disadvantages

a. The original construction cost per acre is great.

b. Trained personnel must direct the growing operation. Knowledge of how plants grow and of the principles of nutrition is important.

c. Introduced soilborne diseases and nematodes may be spread quickly to all beds on the same nutrient tank of a closed system.

d. Most available plant varieties adapted to controlled growing conditions will require research and development.

e. The reaction of the plant to good or poor nutrition is unbelievably fast.

The grower must observe the plants every day. Wignarajah (1995) gave the following advantages of hydroponics over soil growing:

1. All of the nutrients supplied are readily available to the plant.

2. Lower concentrations of the nutrient can be used.

3. The pH of the nutrient solution can be controlled to ensure optimal nutrient uptake.

4. There are no losses of nutrients due to leaching.