Leafing is one of the most misunderstood techniques
of drug Cannabis cultivation. In the mind of the cultivator,
several reasons exist for removing leaves. Many feel that
large shade leaves draw energy from the flowering plant,
and therefore the flowering clusters will be smaller. It is
felt that by removing the leaves, surplus energy will be
available, and large floral clusters will be formed. Also,
some feel that inhibitors of flowering, synthesized in the
leaves during the long noninductive days of summer, may
be stored in the older leaves that were formed during the
noninductive photoperiod. Possibly, if these inhibitor-laden
leaves are removed, the plant will proceed to flower, and
maturation will be accelerated. Large leaves shade the inner
portions of the plant, and small atrophied floral clusters
may begin to develop if they receive more light.
In actuality, few if any of the theories behind leafing
give any indication of validity. Indeed, leafing possibly
serves to defeat its original purpose. Large leaves have a
definite function in the growth and development of Can-
nabis. Large leaves serve as photosynthetic factories for the
production of sugars and other necessary growth sub-
stances. They also create shade, but at the same time they
are collecting valuable solar energy and producing foods
that will be used during the floral development of the
plant. Premature removal of leaves may cause stunting,
because the potential for photosynthesis is reduced. As
these leaves age and lose their ability to carry on photo-
synthesis they turn chloro tie (yellow) and fall to the
ground. In humid areas care is taken to remove the yellow
or brown leaves, because they might invite attack by fun-
gus. During chlorosis the plant breaks down substances,
such as chlorophylls, and translocates the molecular com-
ponents to a new growing part of the plant, such as the
flowers. Most Cannabis plants begin to lose their larger
leaves when they enter the flowering stage, and this trend
continues until senescence. It is more efficient for the plant
to reuse the energy and various molecular components of
existing chlorophyll than to synthesize new chlorophyll at
the time of flowering. During flowering this energy is
needed to form floral clusters and ripen seeds.
Removing large amounts of leaves may interfere with
the metabolic balance of the plant. If this metabolic change
occurs too late in the season it could interfere with floral
development and delay maturation. If any floral inhibitors
are removed, the intended effect of accelerating flowering
will probably be counteracted by metabolic upset in the
plant. Removal of shade leaves does facilitate more light
reaching the center of the plant, but if there is not enough
food energy produced in the leaves, the small internal
floral clusters will probably not grow any larger. Leaf re-
moval may also cause sex reversal resulting from a meta-
bolic change.
If leaves must be removed, the petiole is cut so that
at least an inch remains attached to the stalk. Weaknesses
in the limb axis at the node result if the leaves are pulled
off at the abscission layer while they are still green. Care is
taken to see that the shriveling petiole does not invite
fungus attack.
It should be remembered that, regardless of strain or
environmental conditions, the plant strives to reproduce,
and reproduction is favored by early maturation. This pro-
duces a situation where plants are trying to mature and
reproduce as fast as possible. Although the purpose of
leafing is to speed maturation, disturbing the natural pro-
gressive growth of a plant probably interferes with its rapid
development.
Cannabis grows largest when provided with plentiful
nutrients, sunlight, and water and left alone to grow and
mature naturally. It must be remembered that any altera-
tion of the natural life cycle of Cannabis will affect pro-
ductivity. Imaginative combinations and adaptations of
propagation techniques exist, based on specific situations
of cultivation. Logical choices are made to direct the
natural growth cycle of Cannabis to favor the timely
maturation of those products sought by the cultivator,
without sacrificing seed or clone production.
