A Practical Approach to Aeroponics
Aeroponics systems differ from conventional hydroponics systems in that they use little to no growth medium. Plants are typically cultivated as bare rooted in the aeroponic chamber or growth module, supported by collars or baskets in the system lid. While this aspect doesn’t differ greatly from DWC or RDWC growing systems, the principle difference is in the nutrient solution delivery system.
Aero systems feed bare rooted plants with a nutrient and oxygen rich mist or fog. The advantage here is that there is a greater surface area for absorption of oxygen along with water and minerals (mist). Additionally, this provides excellent control over air to water ratios in the root zone, as roots can remain suspended in moist air rather than submerged in nutrient solutions.
Some aeroponics systems use internal sprinklers or sprayers to blast roots with droplets of nutrient solutions. These types of systems can be inexpensive to build and can operate reasonably well. However, its debatable as to whether this is really aeroponics as there is no mist or fog feeding the roots. The roots are getting hit with drops of water instead, similar in size to what emitters in drip irrigation deliver. The reduction in cost and relatively simple design come at the expense of sacrificing surface area for oxygen delivery and precise control over air to water ratios at the roots.
High pressure aeroponics systems (HPAs) deliver nutrient solutions through mist heads (requiring higher operating pressures) to produce ultra fine mists or fogs to bare roots. With HPA there is much more potential for oxygen absorption by roots and a much higher level of control over air to water ratios in the root chamber of growth modules.
HPA systems can stimulate very rapid plant development and use very little water and nutrients to do so.
For example, a typical misting cycle in the root chamber for aeroponic plant propagation is 20 seconds on and 5 minutes off. The actual volume of solution being delivered each cycle is low, however, it saturates the rooting chamber with an oxygen rich nutrient mist. Any run off solution can be collected and recirculated.
For rooted plants, the misting cycle may remain only 20 seconds on with the duration widening to 8, 12 or even 20 minutes. The bare roots structures themselves act as reservoirs for moisture, oxygen and nutrients; each msiting cycle replenishes their levels to optimal.
To view different HPA system configurations Click HERE