Why is there so many opinions about defoliation?

I was thinking about defoliation on all my plants I was reading something online about this grower who is gradually plucking leaves off through flower week by week and then around five or six he takes about all of the leaves off and he’s yielding pretty high numbers. My question is why is there so many opinions on defoliation I don’t have enough grows under my belt to know which is better, to do it or not to do it. However in my opinion I would think it either works or it doesn’t. If someone can give me some better insight it would be appreciated

most growers usually clean up their plants 2-3 weeks in flower ,I continuously pick leaves off from day 1 ,I grew hundreds of crops ,try it go slow then give the plants time to recover which for me is fast I do only hydro

You don't see farmers out there taking leaves off their plants? Cannabis is no different.

The reason there are so many opinions is called "cognitive dissonance" or could be referred to as "confirmation bias". Kinda like the way people reject science and insist flushing their plants makes them better.

I'm all for a little selective pruning to allow better air flow, or light penetration if needed. Every side by side I've seen where people "defoliate" and strip the leaves from the whole plant, the defoliated plant has always produced less.

Sure some of these guys pull great weight and great buds, but I feel confident they would actually pull better weight and buds if they didn't strip the plants completely.

Everytime you strip the plants bare they spend the next few days focusing growth on making the leaves big enough to start absorbing light again. Instead of working on bud growth.

Almost every time I see people strip the whole plant, they also get extra stretch from the plant reaching for more light.

I am a fan of defoliation. I use it lots.

In the space I work in proven to be great.

In my 3x3 tent I can pull more over-all weight by letting bushes grow thick. But I would say the quality of the bud is lower. Lots of under developed stuff. Due to the fact that In a tent like mine they get so crammed the light gets cut off solid.

I get say 12-14 Oz of really nice bud when pruning a cutting.

If I grew them “un-touched” I could get 16+Oz. But maybe 8-10oz of primo looking buds.

Maybe I’m shallow. I like looking at pretty buds in a glass jar.

What about if you let them go for about 7 weeks after the buds have gotten most of their size. Then defoliate and let the light penetrate down to the lower buds for the lat couple of weeks with that be beneficial?

I never trim a single leaf. Others can do what they want.

Midnight Warrior said:

You don't see farmers out there taking leaves off their plants? Cannabis is no different.

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Big difference between sunlight and artificial. The light penetration of artificial light is limited which is why people remove leaves, lst and scrog. It's not necessary with sunlight because the light intensity is the same at the bottom of the plant as it is on the top.
They prune trees don't they?

MickFoster said:

Big difference between sunlight and artificial. The light penetration of artificial light is limited which is why people remove leaves, lst and scrog. It's not necessary with sunlight because the light intensity is the same at the bottom of the plant as it is on the top.
They prune trees don't they?

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Lots of cultivars are pruned and it's a very proven technique. Pruning can help air flow and light penetration. It can help I text growth to other parts of the plant. I especially will use pruning in veg to help shape the plant and control growth. Peach farmers even remove extra bud sites to direct growth towards the remaining sites.

I don't know of anyone other then cannabis growers that "defoliates". Defoliation implys massive leaf removal, usually stripping the plant nearly bare. It's easily observed that the first thing the plant does in response is direct growth towards making new leaves and/or making the existing leaves big enough to do the job the plant NEEDS them for.

If you don't want popcorn buds, then trim those small useless bud sites out. That will direct the plants growth towards the remaining sites.

Usually defoliators also remove these lowest bud sites and clean up the bottoms. I believe that is where they actually get the claimed "better quality" buds and no popcorn. If the just selectively pruned the plants instead of shamelessly stripping them naked they could get better yields and better quality with little to no popcorn buds.

MickFoster said:

Big difference between sunlight and artificial. The light penetration of artificial light is limited which is why people remove leaves, lst and scrog. It's not necessary with sunlight because the light intensity is the same at the bottom of the plant as it is on the top.
They prune trees don't they?

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With the exception of a few leaves here and there, why on earth would you strip your plants bare?

I saw a garden recently where this new hydro grower was plucking fan leaves in order to 'expose the lower buds to more light'. My first thought was 'why do you have lower buds? You should learn how to prune a plant properly for indoor growing'.

What was interesting was the weird, leafy growth growing directly out of her flowers near the tops of the plants. Basically the plants were growing more leaves out of the buds to compensate for the leaves she had stripped off. That makes sense. The plant NEEDS leaves for photosynthesis which converts solar energy into chemical energy the plant can use.

So when it comes to plant energy, would you rather have it go towards growing more leaves or producing bigger flowers?

I think once universities start intensively studying cannabis specific horticulture and subsequently offering cannabis specific horticulture classes to aspiring farmers we will see a lot of the stoner myths and bro science go the way of the dodo.

Thundercat said:

Everytime you strip the plants bare they spend the next few days focusing growth on making the leaves big enough to start absorbing light again. Instead of working on bud growth.

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This really hits the nail right on the head...thanks Thundercat. You pluck a leaf and the plant grows one back.

Under scrog tents where mold could be an issue...OK.
JD

Thundercat said:

Lots of cultivars are pruned and it's a very proven technique. Pruning can help air flow and light penetration. It can help I text growth to other parts of the plant. I especially will use pruning in veg to help shape the plant and control growth. Peach farmers even remove extra bud sites to direct growth towards the remaining sites.

I don't know of anyone other then cannabis growers that "defoliates". Defoliation implys massive leaf removal, usually stripping the plant nearly bare. It's easily observed that the first thing the plant does in response is direct growth towards making new leaves and/or making the existing leaves big enough to do the job the plant NEEDS them for.

If you don't want popcorn buds, then trim those small useless bud sites out. That will direct the plants growth towards the remaining sites.

Usually defoliators also remove these lowest bud sites and clean up the bottoms. I believe that is where they actually get the claimed "better quality" buds and no popcorn. If the just selectively pruned the plants instead of shamelessly stripping them naked they could get better yields and better quality with little to no popcorn buds.

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Midnight Warrior said:

With the exception of a few leaves here and there, why on earth would you strip your plants bare?

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I think people use the term "defoliate" when describing almost any type of leaf removal regardless of the amount - I doubt that most people who use the term actually mean stripping the plant bare. I remove leaves almost daily but I don't consider it defoliation. I wasn't advocating defoliation in my post and I have never defoliated a plant to compare the yield so I can't really comment on whether it's a good thing or not. I certainly won't comment based on someone else's opinion.

Midnight Warrior said:

You don't see farmers out there taking leaves off their plants? Cannabis is no different.

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Um, yes you do see farmers taking the leaves off their plants. Its called harvest. Ask anyone that has grown brassicas why it is important to "pick the leaves" even if its just going to compost.

In addition to reallocating energy from foliage to fruit production, defoliation in cannabis also sends important hormonal signals to the plant that increase fruit size and potency and speed.

Defoliation should be broken down into two categories: indoor and outdoor.

Outdoor: defoliation is less important for light concerns as sunlight penetrates to the ground. Foliage helps protect plant from elements, creates suction (larger plants need more suction to deliver water and nutrients) and aid in respiration. Still, fairly liberal defoil should be considered, especially in the epicenter of the plant. But sunlight is harsh...

Indoor: foliage is largely extraneous for reproduction. The elements are under your control. Plants size reduces the imperative for suction. Artificial light does not penetrate the way sunlight does (not even close), so the imperative to facilitate light penetration becomes the driving imperative. The luxury of controlling the elements means the grower can manipulate the focus of the plant's energy to grower's designs (lots of potent fruit).

There is some validity to the gradual method of defoliation. However, the "recovery time" gradual defoliators constantly site as a reason for gradual defoliation can be completely mitigated by simply upping the plant's micronutrient regimen immediately following comprehensive defoliation.

All-at-once comprehensive defoliation is one of the most powerful methods for robust harvests, if not the single most powerful method. Defoliation can't kill the plant. Period. The only potentially "negative" side effect is that plant stores micronutrients in foliage. Easily accounted for in feeding regimen, and even if it wasn't, plants would not suffer. Grower however would suffer a slightly longer flowering period, say, 7 days.

Here's a timelapse of a comprehensive defoil:

Another important point in defoliation: many growers have probably noticed how the plant will start dropping leaves from the bottom up (usually accompanied by a yellowing in said leaves, as photsynthesis adjusts to the plant's imperative to reproduce), as plant approaches 3 week of flower. The plant is literally defoliating itself! Our job as human psuedo pollinators is to aid and assist the plant's arduous defoliation process.

*wintermute* said:

Indoor: foliage is largely extraneous. The elements are under your control. Artificial light does not penetrate the way sunlight does (not even close), so the imperative to facilitate light penetration becomes the driving imperative. The luxury of controlling the elements means the grower can manipulate the focus of the plant's energy to grower's designs (lots of potent fruit).

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You can actually see in the video that your statement above is completely false. Once the leaves were removed the plants grew more leaves. It's quite clear in the video that they stunted their plants (maybe that was their goal - to control the stretch?) and IME that is never the best way to grow top quality product or to produce good yields.

homebrewer said:

You can actually see in the video that your statement above is completely false. Once the leaves were removed the plants grew more leaves. It's quite clear in the video that they stunted their plants (maybe that was their goal - to control the stretch?) and IME that is never the best way to grow top quality product or to produce good yields.

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If you say so. A billion dollar industry strongly disagrees.

The new leaves all have one thing in common- they are serving the plant's reproductive process. Not vegetative growth. I don't grow leaves, unless you know someone buying em. I grow fruit.

(maybe that was their goal - to control the stretch?)



"stretch" = vegetative process. not reproductive. This is a broad oversimplification, as hormones are at play.

In this industry, or even just the artistry of cultivation, there are opinions, preferences and empirical facts. All growers should suss out the difference or at least stop the dissemination of flawed notions as expertise.