Hydrolife Magazine June/July 2017 (USA Edition)

grow
How to Increase Oxygen for the Root System in Soil
To increase a soil’s oxygen capacity, a grower can add a
variety of soil amendments. Perlite, pumice, hydroton, or
any other porous substance can significantly increase a
soil’s ability to harbor oxygen. Coco coir is another soil
amendment praised for its ability to not only hold oxygen,
but also have good water retention. Most prepackaged
soil mixes will contain at least one amendment aimed at
increasing aeration. However, it is not a bad idea for indoor
growers to add more aeration amendments to a soil mix. In
fact, well-aerated soil can provide two advantages. First,
well-aerated soil increases the soil’s ability to hold oxygen,
thus providing the plant’s root system with all the oxygen it
needs to grow and flourish. Second, well-aerated soil will
need to be watered more frequently, which gives the indoor
horticulturist the opportunity to implement a more aggressive
feeding regiment. A good rule of thumb is to mix three to four
parts prepackaged soil to one part perlite or other aerating
amendment. This ratio will create a fast-draining soil that
can hold a high amount of oxygen.
“THERE IS A VAST
INVISIBLE WORLD
LIVING IN AND
AROUND THE
ROOT SYSTEM
OF VIRTUALLY
EVERY PLANT
ON THE PLANET.”
How to Increase Oxygen for the Root
System in a Hydroponic System
It is crucial in hydroponic systems to focus on the
temperature of the nutrient solution and mechanical aeration.
The nutrient solution is usually contained in a reservoir,
which needs to be mechanically aerated. Submersible pumps
or air pumps that inject air into the reservoir are the best
ways to replenish dissolved oxygen. Temperature is another
crucial factor affecting the dissolved oxygen content of the
nutrient solution. The ideal temperature for most hydroponic
systems falls in the 65-70°F range. As the water temperature
creeps above 75°F, its ability to hold oxygen diminishes.
This is why water chillers are an essential piece of
hardware for any hydroponic system where the roots are
fully submersed. In other hydroponic systems, the plant’s
root system will be contained within some sort of inert
medium. There are many different hydroponic specific media
available and they all have one thing in common: the ability
to hold a good amount of oxygen.
NUTRIENTS
Aside from increasing the amount of oxygen provided to
a plant’s root system, a grower can pay attention to the
nutrients that will play a role in root health. A good blooming
fertilizer will usually contain the nutrients needed for
healthy root growth. Phosphorus and potassium are the two
main nutrients associated with root growth. Many growers
like to use a blooming base fertilizer in the clone and early
growth stages. A blooming base fertilizer is likely to contain
a higher ratio of phosphorus and potassium to nitrogen
than a vegetative base fertilizer. Phosphorus and potassium
encourage plants to put out new root shoots and help to
strengthen existing roots as they continue to develop. A
diluted bloom fertilizer (one-quarter normal strength) makes
a great nutrient solution for aerobic clone machines or for
conditioning stone wool or other clone media.
ROOT STIMULATORS (HORMONES)
Plant hormones, known as auxins, can also be used to
stimulate root growth. A couple of hormones commonly found
in rooting gels are indole butyric acid and naphthylacetic
acid. These two hormones are considered root stimulators.
Although some growers will use these hormones to stimulate
root growth in early vegetative stages, I have only used
them to stimulate new roots on cuttings. Auxins are known to
promote lateral root development so they are more suitable
for cuttings versus seeds.
28 grow. heal. learn. enjoy.
myhydrolife.com