1. We are currently experiencing issues with viewing and uploading images, our team is working on the issue.
    Dismiss Notice

Defoliation - removing fan leaves for higher yield

Discussion in 'Newbie Central' started by accountant, Jul 26, 2010.


    accountant Member

    added pics (not mine)

    In short, this means removing fan leaves after the stretch ends (around 2 weeks after 12/12.) This allows more light to hit the middle and bottom of the plant. The "fan leaves" you are looking to remove are the big ones that shade smaller leaves or bud sites below them. Some people believe that removing leaves stunts growth but I have never experienced this.

    day 16 flowering BEFORE

    day 16 flowering AFTER

    day 20

    day 25

    day 28

    day 32

    day 40

    Over at icmag there's a popular sticky regarding defoliation as a technique to get higher yields. I was skeptical but the feedback on the thread (with pics) has been very positive.

    So far I noticed some things.

    1) Removing fan leaves does not harm the plant. They grow back within 5-7 days.

    2) More light gets to the bottom of the plant, and so the smaller normally popcorn buds grow dense.

    3) there is a lot more airflow and humidity drops.


    Wait 12-14 days after inducing 12/12, until the stretch has slowed down. Removing leaves before this may cause the stretch to be more than usual.

    Begin by removing any and ALL fan leaves that are shading any other leaf. Basically, remove any big leaves blocking light or bud sites.

    Keep doing this until there is nothing being shaded. Your plant will look naked, with bud sites and small leaves and stems, no fan leaves.

    Place the plants back under 12/12. Your first defoliation will result in removing A LOT of fan leaves!

    Check up on the plants every week, removing any new leaves that are shading areas of the plant.


    We don't really know. A lot of people claim that the leaves are "solar panels" which create energy the plant needs for bud, but the truth is that this is just a guess and in experiments (over at icmag), removing fan leaves did not slow down growth, nor did it reduce yield (it increased it in almost all cases.)

    It might be that removing a big fan leaf lets light go down to a lot of other smaller leaves, thereby increasing the light the plant is getting because smaller leaves have a higher surface area than bigger fan leaves.

    The leaves store nutrients, but indoors, we provide the plant with ample nutrients and so storage is not required as it would be in nature.

    The plant may focus on bud production in flower, rather than focusing energy on making more fan leaves (which doesn't make sense if the plant feels it's about to die.)


    Should I do this in veg? Yes, you should begin doing this when the plant is about 6-8" tall. This helps because subsequent defoliation becomes easier and quicker. Also, in my experience (and others), you may do it anytime during flower, though you would get the most benefit at the beginning of flower (after the stretch, so 12-14 days into flowering.)

    Will potency be affected? No.

    Will yield always increase? No. This depends on your lights and how you trained your plants. The basic idea is to have as much light as possible hitting as many bud sites and small leaves as possible. Outdoors, the sun does not suffer from the same shortcomings as indoor lighting (the further you get from the light, the less lumens you get, at a square inverse.)

    Can I do this outdoors? You may but it probably won't help. See comment above.

    Will the plant die if I remove leaves? No. Some strains may not like being defoliated but I have not come across any in my own experience nor in anyone else's on the original defoliation thread.

    Are there other benefits? Yes! Defoliation helps reduce moisture the plant is giving off, meaning your dehumidifier needs to work less, and it also increases air flow meaning better temps, better air exchange, and less susceptibility to pests and disease that thrive in high humidity/stale air.

    Another benefit is that there is far less trimming required after harvest!

    I've gone through the original thread, asked a lot of questions and did my own experiments. Reply with any questions you might have, and I advise you to try removing some fan leaves from 1-2 plants just for testing. This technique is valuable and I would like to see it spread away from icmag and into the rest of the scene.

    Peace & smoke

    update: see this RollItUp member's view on defoliation:
    GreenLogician and cymbaline like this.

    homebrewer Well-Known Member

    It's the blind leading the blind-er. :lol:
    Uncle Ben

    Uncle Ben Well-Known Member


    Stupid is as stupid does.

    accountant Member

    Any of you guys actually tried it? I've never heard of anyone who tried it actually bad mouth it.

    Keep growing leaves and popcorn buds.

    homebrewer Well-Known Member

    When I was a new grower, I tried everything from '72 hours of dark' to 'the nail through the stalk' in order to produce big buds. You know what actually works? An understanding of how the plant functions and what the plant needs in order to produce those big flowers we chase.
    GreenLogician, Merlot and docter like this.

    accountant Member

    OK. I don't disagree with you, but here's where I'm puzzled: Answer me this. Why is it that if I remove most/all of the fan leaves during flowering, I get an increase in yield from around 0.7-0.8 GPW to close to 1.0 GPW?

    At the very least, defoliating does not have any adverse affect on any of my plants (I tried it on MK Ultra and Skunk #1)

    cymbaline Active Member

    my friend swears by removing the big fan leaves.. I tend to think with the solar panel crowd.
    Would be interesting to see side by side pics of this done through flowering into harvest.

    homebrewer Well-Known Member

    Comment removed
    Uncle Ben

    Uncle Ben Well-Known Member

    Because you see what you want to see. You need to read a book on botany.

    You will NOT get an increase during flowering by removing healthy fan leaves. It is botanically impossible. Bud sites don't have enough photosynthetic material to begin to compete with large fan leaf photon collectors.

    Kassiopeija, Six9 and Merlot like this.

    ganjaluvr Well-Known Member

    Thanks for the article.. and whatever.

    want some advice? Try using side lighting.. ;) It eliminates the need to trim leafs.

    Bottom line is, cutting a plant's leaf's off while its still growing.. does stun the plant.

    It's counterproductive and slows things down, because the plant has to focus more energy on trying to repair itself.

    period.. ;)

    its not rocket science.. its common sense.

    good luck.


    TheGreenBiologist Active Member

    Great Thread! I do this everytime for the exact same reasons! I feel like I'm growing a bonzai tree, I'll sit there staring at my plants for 5-10 minutes sometimes before making a single snip haha

    accountant Member

    added pics from icmag.com/ic/showpost.php?p=3720641&postcount=878

    rastakolnikov Well-Known Member

    Good to see you did your research ;)

    jimmy130380 Well-Known Member

    i agree with ya and will be doing this tomorrow on my plants

    darkdestruction420 Well-Known Member

    why not just cut all the bud leaves off too? then the buds will get more light than if all those pesky leaves werent in the way........

    suTraGrow Well-Known Member

    i loled!!!!!!

    PussymOneyWeed Well-Known Member

    Just remember guys, There not YOUR plants he's fucking up. The blind leading the blind comment about sums it up.

    Dwezelitsame Well-Known Member

    i have tried it and i think its good i dont like the feedback i get from the nonbelievers so i just keep it to myself

    there is like four main fans near top of each bud sight dont remove them

    good luck
    BabyAndaconda420 likes this.
    Lil Czr

    Lil Czr Well-Known Member

    If that is an increase over your normal harvest, then you should go back to square one and pay more attention.

    These threads are almost as bad as bad as "grow weed with incandesant light bulbs"

    I guess the power of suggestion is a stumbling block for some.
    Kassiopeija likes this.

    darkdestruction420 Well-Known Member

    It hurts to see people mutilate their plants to try to fix not having suffecient lighting. If thats not an option their is still a better solution.....Tie the leaves out of the way, it takes about 5 seconds and requires string and tape, anyone could do it and doing so doesnt diminish its energy capabilities or stun the plant or throw away all the valuable stored energy in the leaves and get the lower buds more light still.

Share This Page