Let me start with "why" to trim.
The general theory with trimming away the large leafs is that, simply enough more light will hit more surfacer area on the smaller leaves that were blocked with the large fan leaves. Therefor the buds that were shaded will grow bigger and the light that was hitting the larger leaves is making its way down more into the canopy. However, will it help your plant produce a larger yield? Im not really sure.
But the theory makes some sense right?
Yes it does, but there is one thing that puts that theory into the "It Might Work" section.
That would be the fact the every plant is going to grow differently, depending on any number of things and this is where "Why Not To Trim" comes into play. Like I said above every plant is not going to look the same, for example my current project has been grown using Low Stress Training. This makes my plant look largely different from many other methods of growing. For that fact alone I have more things to take into consideration when i ask my self if I should trim my fan leaves and here is a short list of what i feel should be your key this to look for if your going to trim your fan leaves.

1. Does you plant have an enough smaller leaves to compinsate for the loss of the leaf(s) your about to trim off?
2. Has you plant had (or have) any signs of stress. You don't want a lot of stress this will hurt your yield so be easy with your girls.
3. Do you know what your doing? Remember this is a plant. Cannabis has a lot of family history and from that history the pant has evolved just like every other living thing has and it can take care of its self. If your not sure the best bet is, let it take care of its self its been that way for a long long time.

I believe if you ask your self these 3 questions before you take the cut of faith you might save your self a big problem of a low yield.

If any one feels that there should be more on this list please feel free to add it. I know i look like a noobie but I've been around this pant for a while now. Im not all knowing by any means but from my crops and yields i seems to know what im doing.

Good information. I'll definitely think about this next time. I totally ruined my first grow because I cut way too many leaves. But I think this time around will be alot better.

i never cut off any fan leaves.... just move em so they can still absorb small amounts of light....if your light is strong enough it will penetrate through these leaves. good point about evolution of marijuana. if marijuana didnt need large fan leaves, it would of removed them throughout its evolution. a large fan leave can store more energy than many small ones.

this can be a touchy subject

DO NOT CUT THEM.
IF you think they are blocking some lights, then get some paperclips and hold them back, if you insist on doing anything, but DO NOT CUT THE FAN LEAVES OFF.

IN MY HUMBLE OPINION, When a large FAN leaf starts yellowing, say it is half yellow, that means in the photosynthesis process, that leaf has ate nutrients, absorbed some LIGHT and made food for the plant and buds and NOW, half of that is gone, or used or consumed. Well, what about the other half? Can not it's energy still be used or consumed?
AND when it is ALL consumed or used, that leaf will naturally just fall off.

AND you say it is blocking LIGHT?
GREAT and GOOD, that means it is getting the LIGHT it needs and deserves more than the other leaves do, to do it's job, to make food and grow.


Years ago I tried removing lower fan leaves to allow more Light to penetrate in. When I did cut them off, the plant went into shock for a day or two, and quit eating or only ate half as much, and just went on "stand by" mode. Then, after a day or two, suddenly I saw that big fan leaf replaced by a new leaf, and I saw my plant use the energy to replace that leaf and grow it back FAST to the size it was, more than it used it to grow the plant bigger and make more buds or bigger buds.

I now believe that removing fan leaves is pointless, and that a leaf has a purpose and will serve that purpose until it is dead. Then it will naturally fall off. You will have small and large lower leaves just naturally wilt and fall off daily.


Don't ever remove fan leaves before harvest for several reasons.

1. The fan leaves MAKE AND STORE energy for the plant. The fan leaves are doing a process called photosynthsis, and it is the most important part or task or job the plant does, to make it grow. They make the FOOD, the sugars and carbs needed to grow.

If you remove a FAN leaf, the plant will stop growing taller until it can replace that removed fan leaf.

Removing a healthy fan leaf is a big waste of time..they are rapided replaced, unless you are in the last 2 or 3 weeks of flowering.


2. Even if the fan leaves are yellowing in late bloom I do not remove them until they are almost ready to fall off. The yellowing in the fan leaves at late harvest is the plants metabolism at work. She is transferring all stored energy in the fan leaf to bud production. It is the easiest source of energy she has late in life. Let that leaf do its job.

The Wrong reasoning is like "I could run faster if I was lighter and weighted less, so I am going to cut my legs off".



From the Growers Bible by Jorge Cervantes:
Leave leaves alone! Removal of healthy leave hacks up a healthy plant. Removing large or shade leaves DOES NOT make plants more productive. This practice DOES NOT supply more light to smaller leaves and growing tips. Plants need all their leaves to produce the maximum amount of chlorophyll and food. Removing leaves slows chlorophyll production, stresses the plant, and stunts its growth. Stress is a growth inhibitor. Remove only dead leaves or leaves that are more than 50 percent damaged.

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May Peace and Joy be your companions.
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