Soilless growing systems where plants such as vegetables are cultivated by exposure to constant supply of nutrient containing fluid are known. Some of the problems associated with such commonly known soilless plant cultivating containers and/or tubes are that the nutrient rich fluid tends to escape through the planting holes in the containers, especially when orientated substantially vertically relative to a ground surface and, as a result of the rich nutrient levels, causes overgrowing of unwanted algae on the outer surface of the containers and/or tubes.
Another problem associated with soilless cultivation of plants is due to the constant exposure of roots to fluid. This means that little or no oxygen is available for uptake by the plant roots. Oxygen is an essential plant nutrient and plant root systems require oxygen for aerobic respiration, an essential plant process that releases energy for root growth and nutrient uptake. Injury from low (or no) oxygen in the root zone can take several forms and differs in severity between plant types.
Soilless plant systems are associated with high capital investment, thus, the higher the density of plants per square meter in a typical soilless greenhouse type environment, the better the financial returns on investment.