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.
