This is the term for a medium or solution with a pH less than 7.0 as measured using a digital pH meter or with litmus paper. A lower pH is more acid.
Adding oxygen to a solution or adding a porous material to grow media to allow more oxygen to reach plant roots.
This method of growing plants suspends the plant roots in the air and fertigates the plants by misting the roots with a nutrient solution. The advantages of this system are that it is a highly oxygenated system and allows the grower to harvest plant roots without removing the plant. One of the disadvantages is that because very little if not zero media is used, the amount of time that the plants can survive in the event of pump failure is very limited. Also, because the plant roots must stay moist at all times, the pump must run continuously or extremely frequently which consumes more electricity and decreases pump longevity. The aeroponic method is used frequently in plant physiology when harvesting roots is necessitated, but due to the disadvantages of aeroponic methodology the commercial use for plant cultivation is limited. Aeroponics for plant propagation, however, is highly popular due to the rapid growth of roots associated with increased oxygen in the rhizosphere and the lack of media required to generate a new plant.