Hydroponics/Soilless Culture

Some may argue with these definitions, as the common conception of hydroponics is that plants are grown without soil, with 16 of the 19 required essential elements provided by means of a nutrient solution that periodically bathes the roots.

Actually, 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.

Most of the books on hydroponic/soilless culture focus on the general culture of plants and the design of the growing system, giving only sketchy details on the rooting bed design and the composition and management of the nutrient solution. Although the methods of solution delivery and plant support media may vary considerably among hydroponic/soilless systems, most have proven to be workable, resulting in reasonably good plant growth. However, there is a significant difference between a “working system” and one that is commercially viable. 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. Jensen (1997), in his overview, stated, “hydroponic culture is an inherently attractive, often oversimplified technology, which is far easier to promote than to sustain.

Unfortunately, failures far outnumber the successes, due to management inexperience or lack of scientific and engineering support.” Experience has shown that hydroponic/soilless growing requires careful attention to details and good growing skills. Most hydroponic/soilless growing systems are not easy to manage by the inexperienced and unskilled. Soil growing is more forgiving of errors made by the grower than are most hydroponic/soilless growing systems, particularly those that are purely hydroponic.