defoliation when in flower

[2Ton]

When a plant is flowering whitch leavs are ok to remove and what ones are not ok?

I use topping, lst and defoliation techniques all the way through the veg and flower. Although i only tend to remove the large fan leaves to expose the lower popcorn buds to get golf ball sized buds down there this pick is just entering week 3 of flower... look

https://www.rollitup.org/attachments/tmp_20352-20170116_1925251895114368-jpg.3877724/

https://www.rollitup.org/attachments/tmp_20352-20170116_1925432034160184-jpg.3877727/

 

[GreenthumbQC]

Approx 3rd week - flower defoliation. days 1-7 after defoliation.

 

[Haze the maze]

Oh that is a beautiful plant...

 

[2Ton]

Approx 3rd week - flower defoliation. days 1-7 after defoliation.

They look great mate... these are from today... iam on week 5 of flower with incredible bulk. Loads of bud sites and covered in resin!!

 

[BobCajun]

I tried cutting all leaf from growing buds at week 8. They came out lacking density. Even though there was leaf on the bottoms of the plants and no significant amount of light was getting through to the pots the upper buds that I clipped seemed deflated. They looked big but when cleaned down you could feel that they were sort of hollow.

Then recently I used 13 hours on some plants for weeks 3 and 4 of flowering to try to increase overall size and what I found was that the leaves on colas got considerably larger than under constant 12/12 and when I went back to 12/12 from weeks 5 on the buds came in huge, due to the bigger leaves. So it seems to me that this is a good method.

I also tried 13/11 for the whole flower cycle before and the buds came out much different, fairly thin with medium yield. This batch with the two weeks of 13/11 have buds that look blown up, like Big Bud strain type buds. They were big even at 8 weeks. Anyway, something to try sometime, 13/11 early to leaf up then 12/12 after that. Could probably do the 13/11 for the whole first 4 weeks, I just used 12/12 for the first two to try to get a quick and solid flowering response.

 

[BobCajun]

I guess I should clarify that the buds with the big leaves didn't get freaky big or anything, just noticeably bigger than with 12/12 all the time. The plants also had a lot more size to them overall.

 

[gr865]

Just finished day 21 of 12/12 and did a good defo, not total but enough that it should recover in a few days.
Super Citrus Haze, it has a bit of heat stress, my new drip system did not work yesterday, doing three watering a day with nutes. So I give it a big watering to day at about 50% runoff, running DTW.

Side shot You can really see the stress from the side. She has already recovered, no more leaf turn under.


WW from the top


WW from the side.

 

[GreenthumbQC]

They look great mate

Thanks, I just harvested. Here is what the final girl looked like.

 

[gr865]

Just want to show that the Super Citrus Haze was not harmed by the drip timer problem. Here she is this morning. I was amazed at how rapidly she recovered. Was with out water for over 16 hrs. Perked up in about two hrs.

GR

 

[Odin*]

 

[BobCajun]

My last batch, which I didn't defol except for right at the end, like the last 3 days, I got a bigger yield than when I defoled more and earlier. But much of the extra yield is fluff bud from the lowers. Got more good bud too though. That was also one where I used 13/11 during early flowering so that may have also been a factor.

So you would likely get more total THC yield with minimal defol except right at the end if at all, but much of it would be in the form of extracts of fluff bud. Still, THC is THC regardless of its source, and more of it is better. The bottoms of these plants were quite dense btw. I did no bottom trimming at all.

 

[Flowki]

My opinion is that it entirely comes down to the growing technique you use and skill at it to see significant yield results, including environment. Defoliation has little to do with yield increase.

If you do two natural plants, let one plant grow and then do a side by side defo you ''may'' get a little more yield due to the natural plants shape and indoor lighting not making the most of it. More yield from a natural shaped plant is a moot result though, from the perspective of increased yields indoor (the very point of defoliation advocates). The increase won't be much on a natural if at all, say 10% as my personal estimate.

If you channel the urge to defoliate into an actual technique (topping for 4 as example) you will at least double the light to leaf surface area at a height where the intensity is highest, you also get more light hitting buds if that's what floats your boat. The yield results of a topped plant vs a natural one have been proven substantial, double or more. Far more than any of the defoliation claims that are subjective at best. If you are not getting the most out of a particular topping/fimming style yet are defoliating your plants you are utterly wasting time and energy mastering the wrong thing that gives marginal increase even if it works.

If you wanted to defoliate a topped plant and compare it to a topped plant that did not get defoliated that's your choice. Other skilled experienced growers have done it and stated it does not work (reduces yield). Some skilled experienced growers have stated it does work but I've never personally seen the side by sides of those, ''take my word for it'' kind of deal. Those growers also say that to make it work you have to know what you are doing and only take the right amount at the right time yada yada. Ask yourself this, why bother trying to find out what the right amount is at the right time (getting it wrong lowers yields) just for the chance at a slight yield increase that such growers have not really shown much evidence exists?.

Cutting big leaves off the top allows more light to get to the middle of plant this is true.. but the light reaching those mid leaves is less intense and you've guaranteed reduced photosynthesis out put levels because of it. The bigger upper leaves that you should have left on (and actually made more of them with a topping technique) will take in the most intense light while any light that does reach down into mid canopy (some light penetrates through leaves) will get caught by the mid level leaves. Using a topping technique will increase your photosynthesis rate far more than targeted defoliation. So you want more upper leaves not less.. you get more by topping in veg, not by removing them in flower ;p.

TLDR:
Topping plants is easy, repeatable and reliable while it is also done in veg so no stress during flower and doubles yield at-least. Defoliation will certainly lower yield if you do it too much while doing it the right way is overly difficult for a yield increase that is not proven or completely blown out of the water compared to topping even if it is.


What i would like to finish on though is some reasons defoliation may increase yield, I think it may be a luck thing. Defoliating would reduce humidity in the room (it may have been dangerously high) meaning the plants could potentially dry out faster> drink more nutes > increase yield slightly. This or something of this nature is where I believe some of the defo yield increases may have came from. How ever, get a dehumidifier, keep the leaves, they drink more and also use more light, even more yield.

Other than that that some people put too many plants too close together and it smothers them. Defoliation in that case is going to allow them to breath better and feel less cramped/stressed for them. That defoliation may increase yields too, but marginally. If you had the right amount of plants with the right amount of spacing you would not need to defoliate and the yield would blow the above out the water. How ever I know that doing lots of small plants in a SOG setup does require defoliation but even they state that it is to reduce bud rot rather than increase yield. The trade off is that they have far more plants/root systems that are quicker to put into flower, so the yield comes from having more harvests per year.

 

[gr865]

My opinion is that it entirely comes down to the growing technique you use and skill at it to see significant yield results, including environment. Defoliation has little to do with yield increase.

I do believe that it has to do with growing technique.
I have been using Vertical growing and defo is definitely a plus. My last grow, even though I had some major problems, my fault, I still got more yield. I believe it has to do with grow space, I grow in a 4x4 tent = 16 sqft floor space, in vertical using a 5 - 40"x22" screens = 30.5 sqft. Here is one of the plants from that grow. This was a five plant grow, with one 400W HPS.

My next grow will also be a five plant vertical grow but I am going to use stacked lights for the grow, a 315W CMH and the lower light will also be a 315, if I can get the right price on it, if not the lower light will be a 400W HPS.
A pic of the screen set up, and the second pic is of the lower light stand, the 315W will hang directly above the lower light, no reflectors just bare bulb.
]

Check out some of the vertical grow here
https://www.rollitup.org/f/vertical-growing.126/
Have seen some great grow using this method.

Over crowding is never a good idea, humidity is one of the biggest factors causing problems, and the lower grow usually results in fluffy popcorn.

So, IMHO, there is a time for defo and many times that are not right for defo.

GR

 

[Flowki]

I do believe that it has to do with growing technique.
I have been using Vertical growing and defo is definitely a plus. My last grow, even though I had some major problems, my fault, I still got more yield. I believe it has to do with grow space, I grow in a 4x4 tent = 16 sqft floor space, in vertical using a 5 - 40"x22" screens = 30.5 sqft. Here is one of the plants from that grow. This was a five plant grow, with one 400W HPS.
View attachment 3900764
My next grow will also be a five plant vertical grow but I am going to use stacked lights for the grow, a 315W CMH and the lower light will also be a 315, if I can get the right price on it, if not the lower light will be a 400W HPS.
A pic of the screen set up, and the second pic is of the lower light stand, the 315W will hang directly above the lower light, no reflectors just bare bulb.
View attachment 3900770 View attachment 3900771 ]

Check out some of the vertical grow here
https://www.rollitup.org/f/vertical-growing.126/
Have seen some great grow using this method.

Over crowding is never a good idea, humidity is one of the biggest factors causing problems, and the lower grow usually results in fluffy popcorn.

So, IMHO, there is a time for defo and many times that are not right for defo.

GR

Not saying that a defoliated plant will not go on to produce but I don't think I'll ever side with the notion that if two plants have the ideal environment, the defoliated one will produce more. I would say that if you are having to defoliate (not saying you personally) it is because the environment is not good enough. Yes it may give more yield in that environment but you would get more yield over all in a better environment if untouched, is the point. It makes more sense to improve the environment/topping technique above all else.

On your pic for example, their are many gaps in the trellis. Those gaps in an ideal grow would all be filled with leaves> Not saying I could do it but just that this would be the priority. It looks like you are losing about 1sqr foot of potential light capture from it. You could plant a small topped plant to fill 1sqr light print and get one or two ounce, maybe more. So if you can fill in your trellis entirely you already gained an ounce per plant at least. For your setup, maybe that means replacing the one pot with two so that both plants will hopefully fill out the entire trellis evenly. If the plants out grew and over lapped each other too much then only at those points a little light defoliation could be done for rot/airflow issues. As long as you didn't veg far too long and have a overlapping mess, that type os slight defoliation would be acceptable to me since it's obviously hard to completely predict growth/fill rate and that slight defoliation is still leaving you with a full trellis/canopy. Basically maintenance.

For a normal flat grow this is my opinion but it I'd look to get the plants as close as safely possible to each other with minimal top leaf overlap and the tops even level for best light intensity. If I look at the canopy I don't want to see through it to the ground, anytime you can it's lost yield (slight gaps aside). So basically weather you are using a trellis, net, stakes w/e, you are trying to get a scrog/sog type canopy. That is why UB topping for 8 is so useful, the lower branches move out in a V shape for good lower canopy airflow while the top canopy spreads out to fill it in (some help with stakes etc can be given to achieve it). Would really recommend any flat grower to stop defoliating and try that technique instead.

 

[gr865]

Not saying that a defoliated plant will not go on to produce but I don't think I'll ever side with the notion that if two plants have the ideal environment, the defoliated one will produce more. I would say that if you are having to defoliate (not saying you personally) it is because the environment is not good enough. Yes it may give more yield in that environment but you would get more yield over all in a better environment if untouched, is the point. It makes more sense to improve the environment/topping technique above all else.

On your pic for example, their are many gaps in the trellis. Those gaps in an ideal grow would all be filled with leaves> Not saying I could do it but just that this would be the priority. It looks like you are losing about 1sqr foot of potential light capture from it. You could plant a small topped plant to fill 1sqr light print and get one or two ounce, maybe more. So if you can fill in your trellis entirely you already gained an ounce per plant at least. For your setup, maybe that means replacing the one pot with two so that both plants will hopefully fill out the entire trellis evenly. If the plants out grew and over lapped each other too much then only at those points a little light defoliation could be done for rot/airflow issues. As long as you didn't veg far too long and have a overlapping mess, that type os slight defoliation would be acceptable to me since it's obviously hard to completely predict growth/fill rate and that slight defoliation is still leaving you with a full trellis/canopy. Basically maintenance.

For a normal flat grow this is my opinion but it I'd look to get the plants as close as safely possible to each other with minimal top leaf overlap and the tops even level for best light intensity. If I look at the canopy I don't want to see through it to the ground, anytime you can it's lost yield (slight gaps aside). So basically weather you are using a trellis, net, stakes w/e, you are trying to get a scrog/sog type canopy. That is why UB topping for 8 is so useful, the lower branches move out in a V shape for good lower canopy airflow while the top canopy spreads out to fill it in (some help with stakes etc can be given to achieve it). Would really recommend any flat grower to stop defoliating and try that technique instead.

This was my first vertical grow and yes I could have filled in the screen better, I will get better at it. Also being my first grow I did not provide enough light to the plant, the lamp during flower is about 1/2 to 1 foot below the canopy line, so the lower plant did not get the light needed. Next grow will be a 5 plant vertical grow with screens with the stacked lighting.

I have seen vertical grows where they went way overboard on the defo and got shitty results, but I have seen some personally that are spectacular with nice buds from top to bottom, no popcorn at all. What was popcorn was the size of a fist. His grow got 1.5 g/W. My best in a horizonal grow, using canopy control was .7 g/W, but I also had inferior lighting, tried making a 400W HPS cover a 4x4.
I have not tried a SCROG yet, maybe someday and when I do I hope you chime in on my grow.

What size is your grow area, don't you have to have a lot of room to do a SCROG, to be able to get around the plant for training?

GR

 

[Flowki]

This was my first vertical grow and yes I could have filled in the screen better, I will get better at it. Also being my first grow I did not provide enough light to the plant, the lamp during flower is about 1/2 to 1 foot below the canopy line, so the lower plant did not get the light needed. Next grow will be a 5 plant vertical grow with screens with the stacked lighting.

I have seen vertical grows where they went way overboard on the defo and got shitty results, but I have seen some personally that are spectacular with nice buds from top to bottom, no popcorn at all. What was popcorn was the size of a fist. His grow got 1.5 g/W. My best in a horizonal grow, using canopy control was .7 g/W, but I also had inferior lighting, tried making a 400W HPS cover a 4x4.
I have not tried a SCROG yet, maybe someday and when I do I hope you chime in on my grow.

What size is your grow area, don't you have to have a lot of room to do a SCROG, to be able to get around the plant for training?

GR

I'm really not trying to put your grow down you've done good. Also hope I don't come off as if I know everything but as said it's of my opinion that no matter what style you grow with, trying to fill out the canopy evenly with as many leaves possible is the best way to increase yields. The right lighting and distance, room control and feed are also big parts of it that should be improved on as priority's, we all do that in our own way and at our own speed/ability. Defoliating a plant that isn't filling out it's footprint I just don't see how that will increase yields. I've seen people who run vertical trellis with reflective sheeting on the back of it so that any light that does penetrate the canopy gets reflected back. That imo is fking genius and will stand more chance of increasing yield over cutting off leaves.

The people who take off too much have shown in pics how bad the plant done. The people who don't take off very much, it's my opinion that they simply have not took enough of the vital leaves off to seriously impact yield. I read once that a person takes off leaves because it forces the plant into some kind of panic/survival mode and makes it put out even more smaller leaves. That could be true but I don't like the idea of doing that to the plant in flower, force it to panic? and spend time/energy on recovering back the leaf area you cut off, rather than being happy and just producing buds the whole time. I've read that stress increases flower time too, so maybe what they say if true is offset by extra time for it to finish flower.

You are basically already doing scrog, it's not worlds apart. When not using a scrog net, topping techniques or lst they are still trying to get a more even canopy like found in your trelis/scrog but ''eyeing'' it up rather than having a physical barrier.

People are able to do scrogs in pretty cramped areas but I think you are right, access looks like a nightmare. And the issue is that when the plant is stretching they seem forced to keep on it and keep tucking. But the reward is a very even filled in canopy.

An easier approach is topping for 8 and using as many plants required to fill in the area. You stake them, 4 stakes per pot and the stakes used to spread/hold out the 4 main branches to spread the canopy and fill in the entire area at flip. After that you need not mess around any more and just feed. You won't have as flat a canopy as with scrog net, maybe get less yield too but the work involved is not near as intensive. However I wonder if it would allow a quicker finish as their is minimal to no stress in flower that way.

One thing I do question over scrog net to a more free flow stake setup as above is light penetration. In scrog they cut off almost everything under the net so if any light does indeed penetrate through leaves theirs no leaves there to make use of it. Aside form that when a fan osculates over canopy it will move leaves around and momentarily create light cracks down the canopy (theory). If you have mid level leaves as with the staked example then you will make use of that light. It may end up swings and roundabouts though, maybe the yields end up similar but trimming mid level buds will take longer so you end up putting in the extra work anyway. Still, would rather be on my ass cutting than on my knees crawling and cutting ;p.

 

[Karah]

I defoliated my last crop, the last 4 weeks of flower. I pulled over 6 lbs from 6 plants. Might just have been dumb luck, or perhaps not. Will defoliate the last 4 weeks of my next crop (putting into bloom in 1 week).

 

[gr865]

I defoliated my last crop, the last 4 weeks of flower. I pulled over 6 lbs from 6 plants. Might just have been dumb luck, or perhaps not. Will defoliate the last 4 weeks of my next crop (putting into bloom in 1 week).

pictures please

 

[gr865]

I'm really not trying to put your grow down you've done good. Also hope I don't come off as if I know everything but as said it's of my opinion that no matter what style you grow with, trying to fill out the canopy evenly with as many leaves possible is the best way to increase yields. The right lighting and distance, room control and feed are also big parts of it that should be improved on as priority's, we all do that in our own way and at our own speed/ability. Defoliating a plant that isn't filling out it's footprint I just don't see how that will increase yields. I've seen people who run vertical trellis with reflective sheeting on the back of it so that any light that does penetrate the canopy gets reflected back. That imo is fking genius and will stand more chance of increasing yield over cutting off leaves.

The people who take off too much have shown in pics how bad the plant done. The people who don't take off very much, it's my opinion that they simply have not took enough of the vital leaves off to seriously impact yield. I read once that a person takes off leaves because it forces the plant into some kind of panic/survival mode and makes it put out even more smaller leaves. That could be true but I don't like the idea of doing that to the plant in flower, force it to panic? and spend time/energy on recovering back the leaf area you cut off, rather than being happy and just producing buds the whole time. I've read that stress increases flower time too, so maybe what they say if true is offset by extra time for it to finish flower.

You are basically already doing scrog, it's not worlds apart. When not using a scrog net, topping techniques or lst they are still trying to get a more even canopy like found in your trelis/scrog but ''eyeing'' it up rather than having a physical barrier.

People are able to do scrogs in pretty cramped areas but I think you are right, access looks like a nightmare. And the issue is that when the plant is stretching they seem forced to keep on it and keep tucking. But the reward is a very even filled in canopy.

An easier approach is topping for 8 and using as many plants required to fill in the area. You stake them, 4 stakes per pot and the stakes used to spread/hold out the 4 main branches to spread the canopy and fill in the entire area at flip. After that you need not mess around any more and just feed. You won't have as flat a canopy as with scrog net, maybe get less yield too but the work involved is not near as intensive. However I wonder if it would allow a quicker finish as their is minimal to no stress in flower that way.

One thing I do question over scrog net to a more free flow stake setup as above is light penetration. In scrog they cut off almost everything under the net so if any light does indeed penetrate through leaves theirs no leaves there to make use of it. Aside form that when a fan osculates over canopy it will move leaves around and momentarily create light cracks down the canopy (theory). If you have mid level leaves as with the staked example then you will make use of that light. It may end up swings and roundabouts though, maybe the yields end up similar but trimming mid level buds will take longer so you end up putting in the extra work anyway. Still, would rather be on my ass cutting than on my knees crawling and cutting ;p.

I am able to remove the emitter and pull the plants out to work on them, much easier then crawling.
The key IMHO, is to remove growth slowly giving time for recovery.

 

[Karah]

pictures please

I posted this pic in a different thread as well but this is maybe 2 weeks before I started chopping. The only leaves I left on my ladies were right around the trellis and towards the underside.