Well thats pretty interesting..
Growing with High-pressure Aeroponics (HPA)
High-pressure aeroponics (HPA) is the most efficient way to grow, as NASA determined with its aeroponic potato production. When this type of efficiency is achieved, roots develop fine hairs called trichoblasts that are more efficient at taking up nutrients and can provide a higher rate of growth than roots growing in other methods. This style also happens to use the least amount of water and nutrients possible, which is what motivated NASA to give it a try, as it looked for ways to minimize cargo costs for space missions.
When cloning or germinating with HPA, it is important to provide the roots with enough humidity so they can develop a strong root system. This is done by setting timing cycles so they are almost always on, or with a shorter ON/OFF ratio than later on in the growth cycle. After roots have developed, it is good to dial back ON times and increase OFF times. This will be done continually, from the time of initial rooting until later in the growth cycle.
Trichoblasts, or “root fuzz,” are allowed to develop only in a finely tuned HPA system that doesn’t oversaturate the roots, which can grow into pom-pom-sized fuzzy masses under the right conditions. Less spray time and wetting causes more oxygenation, leaving the roots with a hyperactive surface area that can absorb more nutrients and water out of the air/vapor mix. Less is more with HPA, so the
feeding solution should be closely monitored.
The same nutrient density used in early veg should also be used throughout the rest of the cycle, as far as EC/ppm levels are concerned. It is important to judge this by the amount of trichoblasts (fuzz) that have developed on the roots. If these are not present, a feeding schedule similar to typical hydroponic and
aeroponic styles can be used.
On the other end of the spectrum, when trichoblasts are prevalent, plants can be burned by the higher density of the nutrients. A good rule of thumb is to reduce nutrients by about 25-50% of normal strength as the plant’s absorption rate increases.