AEROPONICS 2.0
A
eroponics 2.0, a.k.a. high-pressure
aeroponics, is different from
the aero systems that first appeared
commercially in the ’90s. These systems
produce a very light mist that floats
around in the air and looks like fog,
so the term fogponics is often used to
describe this style of growing.
In a fogponics system, water and
nutrients are atomized and distributed
in a mist with droplets in the range of
30-80 microns. A droplet of 50 microns
is the optimal size roots can uptake,
as dete rmined by NASA’s research on
aeroponic potatoes in the International
Space Station during the ’90s. Because
most droplets in this range are lighter
than air, they float around the root
chamber until colliding with roots or
other obstructions. The root chamber
remains humid with roots dangling
in air, which is why it is called an
aeroponic system.
For the atomization and mist to occur,
an external, high-pressure pump is
needed instead of the submersible,
pond-style pump that is typically used in
aero systems and usually produces low
pressures (under 4 psi). To produce the
mist or fog, pumps must run pressure
in the range of 80-100 psi. Low-pressure
aeroponics uses low-pressure, highflow pumps, whereas high-pressure
aeroponics uses high-pressure, low-flow
pumps. For this reason, the mist is
extremely gentle and floats around like
a fog in a properly tuned high-pressure,
aeroponic system.
In a fogponics system,
water and nutrients are
atomized and distributed in
a mist with droplets in the
range of 30-80 microns.”
104
Maximum Yield USA | November 2015
High-pressure aeroponics is the most efficient way to grow.
Ultrasonic Foggers
There is another kind of fogponic
system that includes the use of an ultrasonic fogger, much like the kind found
in humidifiers. With an ultrasonic
fogger, a small ceramic plate is vibrated
by an oscillator more than one million
times per second and creates droplets
only 3-5 microns in size. This thick fog
can actually suffocate roots because it
displaces available oxygen. However,
if the root chamber is well-aerated
and properly cooled, the roots will be
under the right conditions to grow.
With enough oxygen and the proper
temperatures, cuttings often root faster
in this type of system. However, with
greater rewards come greater risks in
the sense that the roots are extremely
sensitive to high-temperatures and lowoxygen levels.
Using a lower dose of nutrients when
using ultrasonic foggers is recommended because the salts of the
nutrients can damage the equipment.
In addition, the nutrient mix cannot
be easily carried in a fog consisting of
such small droplets. For this reason,
this type of set-up is best suited for
propagation and early vegetative cycles.
For flowering or fruit production,
nutrient-craving plants perform much
better with a droplet size closer to
50 microns, which can fully support the
plant’s hunger for nutrients.
Growing with 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