screwdriver said:
I agree with Stoney Bud for the most part.
It is causing a little stress to remove the leaf and you can remove up to 30% in trimming. To me that's a lot. The reason I trim fan leaves is air flow. My canopy can be so dense I have had a dying off of fan leaves.
I grow indoors in a small cabinet I find it better to occasional trim some fan leaves and bud sites than to leave it to grow wild. I can't imagine that I'm gaining or losing that much so I call it even. I also LST which causes stress to the plant. I grow the plant to my needs as much as its needs.
It's not me that is thinking this up. I'm only quoting what every plant biologist on the planet has found to be true.
You should trim NO leafs. When a leaf browns or yellows, and the plant is healthy, it's it's because the plant has grown to a point where the yellowing leaf is no longer getting light as a result of other leaf that has grown further up on the plant. This is a natural thing and in no way affects the growth of the plant.
When healthy leaf yellows, just let it fall naturally from the plant. It will do so right after it no longer supplies the plant via photosynthesis.
LST means "Low Stress Training" and can be done to redirect the plant to fill out a growing area.
"Trimming" using the 30% rule is to keep a host plant at a manageable size and not to a plant that is being grown for bud.
I'll say it again; You should NEVER cut healthy leafs from a plant that you are growing for bud. It harms the plant. This has been proven so many times in studies that it's just not worth arguing over. It's a proven fact of plant biology.
There are individual reasons to trim or cut leaf from a plant, but none that are to promote better growth of bud.
Leave your light gathering leaf alone. Take them when they are half or more than half dead. The plant cannot heal the dead leaf, but will continue to attempt to do so by creating and sending a "Healing Hormone" to the injured area until it does fall off and the stub is healed. If it's already half dead, just remove that leaf as gently as possible and it will enable the plant to heal the stem faster and save more energy for other growth. Up until the leaf is half dead, it's still providing enough photosynthesis to be worth it to the plant. After half or more is dead, it no longer is a viable leaf and is costing the plant more than it can produce via photosynthesis.
All of this information can be verified by investigating the appropriate areas of plant biology. Start "Googling" and you'll find it. Or, many books are available on the subject.
