Hydrolife Magazine April/May 2017 (Canada Edition)

grow
In cannabis cultivation, as in life, there
are two types of stress—good and bad.
Good stress causes the cannabis plant
to work harder to achieve a desirable
goal (larger buds, anyone?); bad stress is
counterproductive to growth and could
ultimately kill the plant. When growing
cannabis, it is important to maximize
the use of good stress and minimize the
introduction of bad stress.
Bad Stress
Some plant stressors are
counterproductive to growth as they
inhibit the plants’ ability to absorb light
for photosynthesis, constrain appropriate
amounts of leaf transpiration, increase
susceptibility to pest/disease attack,
and potentially cause the plants
to develop genetic abnormalities
(hermaphroditism); all of which could
devastate an entire flower crop.
Light
When flowering, cannabis plants
are very susceptible to stress from
interruptions in the light cycle. Even
a red indicator light on a camera can
cause plants to become hermaphroditic.
As such, it is crucial to maintain
complete darkness during the entire
lights off cycle. Because commercial
operations require cameras in every
room of the grow, look for cameras and
other emergency lights that have green
indicator lights instead of red and then
securely cover the light with a piece
of electrical tape. The photoperiod of
cannabis plants is largely unaffected
by low intensity green light, making it
the better choice of light source for dark
cycle work lights and indicators. Now,
don’t mistake the previous statement as
“Cannabis plants don’t use green light
for photosynthesis.” They very much do.
However, there are different chemical
processes within the plant that are at
play when it comes to photoperiodism.
If work must be completed during the
lights off cycle, only use a low power
green LED for a light source. When no
work is being completed in the flower
room, the space should be completely
dark and tested regularly to
verify that no new light leaks
have developed.
Temperature
Within the conventional indoor grow
environment, heat is typically much more
of a negative stressor to cannabis plants
than cold. Cannabis plants grown indoors
aren’t usually exposed to temperatures
below 10°C, so seeing stresses caused by
plants getting too cold is an uncommon
event. However, when ambient conditions
rise above 29°C, the plants start to alter
their growth patterns to accommodate a
higher rate of transpiration to keep the
plant cool. This altered growth puts extra
energy into growing more plant stem,
ultimately resulting in a lanky plant
without the desired flower mass yield
and essential oil production. At extremely
high temperatures, photosynthesis can
cease entirely and maturation of the crop
will certainly be delayed. Keeping the
temperature and humidity of the room at
an appropriate level throughout the day is
crucial to maintaining an efficient grow.
Good Stress
There are a variety of good types of stress
that can be introduced throughout the
growing cycle. Exposing cannabis plants to
good stress will result in robust plants that
are more likely to produce more resin and
larger buds. The best plants are the ones
that not only survive doses of good stress
but actually thrive on it. To ensure you are
growing the best plants, it is important to
cull plants at each stage of growth.
Air Circulation
Using air circulation is the most common
way of stressing plants that most people
already incorporate in their room for other
reasons. By using an oscillating fan to keep
young plants moving with forced air, you
are, in effect, constantly providing small
stresses to the stem of the plant that help
the stem become thick and robust more
quickly than if forced air is not used.
“
KEEPING THE TEMPERATURE & HUMIDITY
OF THE ROOM AT AN APPROPRIATE LEVEL
THROUGHOUT THE DAY IS CRUCIAL TO
MAINTAINING AN EFFICIENT GROW.”
Plant Training
Plant training is the process of managing
plant growth using various levels of
applied stresses to manipulate the plant
shape and size. These stressors alter
growth by changing the plants’ nutrient
distribution pathways, modulating metabolic
rates, and by physically spreading
the plant out laterally, making it easier
to maintain an even canopy. There are
several ways of achieving this end. Some
may seem extreme, but they’re worth experimenting
with if you haven’t already.
26
grow. heal. live. enjoy.
myhydrolife.ca