Dimming Lights Towards End Of Bloom

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DrFever

DrFever

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Its was actually the stitching institute that did tests and found higher THC with 72 hrs off but also mentioned that it worked on some strains not all .. i have shut it down for 72 hrs and think that of course your going to gain some resin production , is it negligible YUP
but as plant stays in darkness the plants batteries are also dieing out so now pending on last day i run lights i may leave plants in darkness or few days for instance friday or sat chop and your plants are done tuesday or wed ...
topo ??? there is always gong to be NPK in your plants no matter what,, lights off is going to do nothing any stress is going to hurt the plant you here a bunch of ice water flush lol , or flushing period etc its just another myth many uutrients are hard to leach from the soil ,, organics why bother flushing same thing with chem just back off last week
 
Topofthecrop

Topofthecrop

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Its was actually the stitching institute that did tests and found higher THC with 72 hrs off but also mentioned that it worked on some strains not all .. i have shut it down for 72 hrs and think that of course your going to gain some resin production , is it negligible YUP
but as plant stays in darkness the plants batteries are also dieing out so now pending on last day i run lights i may leave plants in darkness or few days for instance friday or sat chop and your plants are done tuesday or wed ...
topo ??? there is always gong to be NPK in your plants no matter what,, lights off is going to do nothing any stress is going to hurt the plant you here a bunch of ice water flush lol , or flushing period etc its just another myth many uutrients are hard to leach from the soil ,, organics why bother flushing same thing with chem just back off last week
Sure there will always be some NPK in your plant. True. But you can minimize by letting the nutrients stay in your soil not in your bugs by letting the plant "sleep" instead of rage and be up taking and holding nutrients in the middle of the day. Think about it...
 
Junk

Junk

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I'll find that study. I do 48 hours of dark, but just because a lot of the better growers do it. I never had any concrete evidence it did anything.

I wonder if that terpene chart showing highest levels at dawn would still apply. My guess would be yes.

The flushing thing I'm still not convinced on. For example, we use blood meal (dried blood) on our plants in soil. Once the plant has absorbed that, it's no longer blood meal. Just like we eat an apple & our body divides it up in the sugars, vitamins etc & sends it where it's needed, it's not an apple anymore. Grass fed beef doesn't taste like grass, & corn fed beef doesn't taste like corn. However, those two do taste different. I use manure in my veggie garden, but my veggies don't taste like horse poop.

I understand the...the best way I can think to describe what the flushers are trying to do is induce a sort of catabolic state so that it's using up the nutes left in the plant. But the plant is not absorbing the nutes in the same form we added them. (go back to the horse poop example) I've tried flushing, & not flushing in soil, & given a proper cure, I don't notice a damn bit of difference. On paper, there may be, but in real life, I don't notice a difference...in soil. The fact that I was organic probably helped, but I'm still not quite convinced.

I'm hydro now, so I will have to see how it works with that. But in soil at least, I just stopped feeding them the last week or so, not to induce that state (I forget the name) but I think it's a waste. There is plenty left in the soil (I check) for the plant to survive on. The soil is getting tossed after, so why waste the nutes.
 
Topofthecrop

Topofthecrop

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I'll find that study. I do 48 hours of dark, but just because a lot of the better growers do it. I never had any concrete evidence it did anything.

I wonder if that terpene chart showing highest levels at dawn would still apply. My guess would be yes.

The flushing thing I'm still not convinced on. For example, we use blood meal (dried blood) on our plants in soil. Once the plant has absorbed that, it's no longer blood meal. Just like we eat an apple & our body divides it up in the sugars, vitamins etc & sends it where it's needed, it's not an apple anymore. Grass fed beef doesn't taste like grass, & corn fed beef doesn't taste like corn. However, those two do taste different. I use manure in my veggie garden, but my veggies don't taste like horse poop.

I understand the...the best way I can think to describe what the flushers are trying to do is induce a sort of catabolic state so that it's using up the nutes left in the plant. But the plant is not absorbing the nutes in the same form we added them. (go back to the horse poop example) I've tried flushing, & not flushing in soil, & given a proper cure, I don't notice a damn bit of difference. On paper, there may be, but in real life, I don't notice a difference...in soil. The fact that I was organic probably helped, but I'm still not quite convinced.

I'm hydro now, so I will have to see how it works with that. But in soil at least, I just stopped feeding them the last week or so, not to induce that state (I forget the name) but I think it's a waste. There is plenty left in the soil (I check) for the plant to survive on. The soil is getting tossed after, so why waste the nutes.
Since your in hydro you should feed your plants the last week the normal ppm that your running in flower then chop your plants for harvest and that shit will taste like nutes and burn your throat to shreds. Yes organic is different. Pardon my French.
 
soserthc1

soserthc1

7,040
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Good read ...don't do darkness for the simple fact I'm impatient. I have ran the same plant with and without a 48 hr dark period before harvest and no difference. If I could utilize a lab and prove it increased resin or terps I would do it but labs are not a option.
I'm becoming curious to a dark period before flower but need to read on it more.
What would be the thinking on this ?
Sorry if it was covered as I skimmed the thread for time.
I just kicked my lights to 11.5 on 12.5 off but mainly for heat and my convenience and thinking on that ,this morning there was a noticeable increase in bud size ....possible it was just a normal increase for time but I do run perpetual and all plants seemed bigger. It was a biowar feed night also
 
Junk

Junk

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Since your in hydro you should feed your plants the last week the normal ppm that your running in flower then chop your plants for harvest and that shit will taste like nutes and burn your throat to shreds. Yes organic is different. Pardon my French.


So have you tried it? I mean, personally, yourself, in what we could infer is a reasonably scientific comparison? It would have to be the same strain, same batch, same diet, light etc. If so, is that what the results were?

I don't want this to become an "intense" discussion, so I'll try to clarify it here; you sound kind of defensive. I'm not saying someone is "right" & someone is "wrong." I'm saying, personally, with hydro, I don't know if it's a noticeable difference. It seems like there def would be. But that is what science is for, to test hypothesis, because often our "logical" conclusions are incorrect. Then we research why, often to find out we did not have or incorporate all the necessary facts. Etc. I need to test it for myself to see.

I found that in soil, I didn't notice any difference, but many people told me I would. I was MORE inclined to believe that I would notice the difference I had heard so many people talk about. But being honest with myself, I really didn't notice any difference. This puts me in opposition to other popular growers who I really admire & talk to frequently. It's not even a solid result. Perhaps my taste buds are not as good, perhaps my neuro disorders affect that part of my brain, who knows. But in soil, I have personally tried it, at least 3 times, & I didn't notice a difference.

If I came across as saying one opinion is ridiculous & the other one sound, that is not what I meant to do. Cool? :)

I can't find that study. All I can find is other posts by Dr.Fever mentioning the study. I'm not saying he didn't read what he claims he did. But, we are kind of back to square one on that count...we don't have access to a scientific study backing it up.

I can't remember what post is where, but I agree with whoever said 72 hours seems like too long. Like I said, I do 48, just because some more experienced growers that I know do it that way. I can't tell a difference...all I think I can tell is that it doesn't harm the plant, so I continue to do it to see if I ever notice any.

Can anyone with one of those 420 scopes or cameras try to take good photos before & after?

I don't think the fact that it doesn't imitate nature really tells us anything. We can take advantage of many things nature doesn't provide. Lighting intensity, spectrums, timing, foliar feeding, hydro, co2 supplementation etc.

That fact that nature doesn't typically provide a similar dark period isn't a logical reason to say it doesn't do anything.

Bottom line, personally, I just don't know.
 
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Topofthecrop

Topofthecrop

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I apologize if I came off defensive. Hard to show facial expressions behind this screen. :)
I'm moving on outta this thread.
 
3N1GM4

3N1GM4

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To add to my previous post, co2 is only absorbed during the time the plant is receiving usable light. Reducing the usable light would likely reduce the amount of co2, nutes and water it could draw in to use during the night to grow. Reducing usable light is bad idea imo. I have heard of several techniques to trick a plant into producing more terps and thc such as the hot water shock, raising temp, or even buring hot coals near the root ball but I would just stick with full power 12/12 myself and maybe 48 hours of dark at the end.
 
3N1GM4

3N1GM4

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Try an experiment, two tents , two identical clones. One dim the lights the last 4 weeks, the other add a big red led grow light to the mix and see which one makes your eyes water.:D
 
C

Chance Last

72
18
So we would only usually turn down our lights the last few days/weeks of flower in the rooms that run a little warm so we can bring temps down and really close/harden the buds. We have also run 10k mh lamps in the past and this absolutely has had an indisputable positive effect on the finished product. You're basically emulating winter in that the days get cooler and the light gets blue-er.

I think that turning down the lights and the effect it has on the plants has less to do with the actual light and more to do with the room temps, this is at least my take on it. I think this goes the same for the 2 days of darkness, just 2 days of cold weather and the plant freaking out thinking winter is coming which stimulates extreme trichome production in hopes of catching pollen to reproduce.
If I was running 4k HPS and turned them all off and hit it with about 2k MH, Would this work alright for me ? Wanted to do the 48h dark for first time so now you made a valid point and I'm thinking that seems more realistic of nature. Thanks!
 
MendoAdome

MendoAdome

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For the last three weeks: Dimming and raising the lights, lowing the pH, decreasing the temps, both air and water all simulate the effects of fall and will signal to your plants that their life cycle is coming to an end and thus increase yield, terp production (increasing the overall quality and aroma)
 
Ytransplant

Ytransplant

14
13
I usually dont make it a habit to comment on forums 2 yrs old, but very recently, I was in a meeting about the subject of reducing light Intensity the last cpl weeks of flower...SO, Maybe someone will still see this and pick up the tip....I see that some do believe it replicates the fall sun better to reduce the intensity...this is of course why red spectrums are better for flowering since THAT DOES replicate the wave length late season....
I also dont make it a habit of posting info unless I am 110% sure about the info I post....One of a growers worse enemy is trusting TOO MUCH in forum info....There are way too many persuasive ppl in forums, that can only grow a good case of toenail fungus...
Spring of 2019 will mark 40 YEARS that I have been growing cannabis hydroponically....There is NOT a scenario, that I have yet to experience in that time.....Now to the subject at hand....reducing light intensity late flower.....It was a cpl decades ago, where seeing, what I call secondary buds, develope better resin densities..these are the buds, lower on the main colas and even the first cpl sets of buds that have a stem with length AWAY from the main stalk....Regardless of strain, this was occurring...why would these big main colas have less resin development than their neighboring buds a little lower....Years of pondering, AND comparisons (and I mean DOZENS), That buds love to be POUNDED with intense light to gain mass up till 5.5-6 weeks, considering strains that finish from 8-9 weeks...AFTER the mass is done, its all about ripening those resins that ALREADY exist....Raising lights was the key before Digital dimmers were available....Now, its a simple flip of a switch....Soon as this was realized, my Main colas were as frosty as my 'secondary' buds....Ripening resins is more of a delicate process than many realize....It is also QUITE POSSIBLE, and the main culprit, to evaporate resin....too intense of a light the last 10 days-2 weeks can cause more harm than good to the buds closest to the light, typically being you best main colas....Resins are a protective response, to UVB, pests, etc, but LATE SEASON in nature, has a sun much lower in the sky with a considerably reduced intesity.....I have seen it to be not as much of a concern when growing with like a 400w HID, CFLs, or other less intense lighting sources....BUT with 600-1000W hid lighting sources, YOU WILL BENEFIT, by reducing the output to finish ripening....I personally run a 1000w HID system...I reduce it to 50% the last 2 weeks and get resins that make your mouth water, all the way to the very top of the tallest colas....Again, not as important with less intense lighting, but VERY IMPORTANT with high output lighting....reduce it!!!... your buds are already as big as they can get, and its time to PAMPER your Trichomes and pump them up to their genetic potential...This is NOT based on scientific data, but is based on 4 DECADES of growing experience....IT WORKS!!!!...YT
 
1diesel1

1diesel1

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I’m going to give this a shot. I run gavitas, I always set my sun up and sun down time to mimic the sun. Thanks for the info! I like it!!
 
crimsonecho

crimsonecho

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I usually dont make it a habit to comment on forums 2 yrs old, but very recently, I was in a meeting about the subject of reducing light Intensity the last cpl weeks of flower...SO, Maybe someone will still see this and pick up the tip....I see that some do believe it replicates the fall sun better to reduce the intensity...this is of course why red spectrums are better for flowering since THAT DOES replicate the wave length late season....
I also dont make it a habit of posting info unless I am 110% sure about the info I post....One of a growers worse enemy is trusting TOO MUCH in forum info....There are way too many persuasive ppl in forums, that can only grow a good case of toenail fungus...
Spring of 2019 will mark 40 YEARS that I have been growing cannabis hydroponically....There is NOT a scenario, that I have yet to experience in that time.....Now to the subject at hand....reducing light intensity late flower.....It was a cpl decades ago, where seeing, what I call secondary buds, develope better resin densities..these are the buds, lower on the main colas and even the first cpl sets of buds that have a stem with length AWAY from the main stalk....Regardless of strain, this was occurring...why would these big main colas have less resin development than their neighboring buds a little lower....Years of pondering, AND comparisons (and I mean DOZENS), That buds love to be POUNDED with intense light to gain mass up till 5.5-6 weeks, considering strains that finish from 8-9 weeks...AFTER the mass is done, its all about ripening those resins that ALREADY exist....Raising lights was the key before Digital dimmers were available....Now, its a simple flip of a switch....Soon as this was realized, my Main colas were as frosty as my 'secondary' buds....Ripening resins is more of a delicate process than many realize....It is also QUITE POSSIBLE, and the main culprit, to evaporate resin....too intense of a light the last 10 days-2 weeks can cause more harm than good to the buds closest to the light, typically being you best main colas....Resins are a protective response, to UVB, pests, etc, but LATE SEASON in nature, has a sun much lower in the sky with a considerably reduced intesity.....I have seen it to be not as much of a concern when growing with like a 400w HID, CFLs, or other less intense lighting sources....BUT with 600-1000W hid lighting sources, YOU WILL BENEFIT, by reducing the output to finish ripening....I personally run a 1000w HID system...I reduce it to 50% the last 2 weeks and get resins that make your mouth water, all the way to the very top of the tallest colas....Again, not as important with less intense lighting, but VERY IMPORTANT with high output lighting....reduce it!!!... your buds are already as big as they can get, and its time to PAMPER your Trichomes and pump them up to their genetic potential...This is NOT based on scientific data, but is based on 4 DECADES of growing experience....IT WORKS!!!!...YT
Glad you brought your 40 years of experience to the farm, welcome.
This observation is only about hid lighting right. Because with leds my tops are the frostiest usually. But the idea of letting it build up resins with less light is nice, i actually shorten the hours too. At the last week or two, i do 10/14, some say it makes them mature faster, some say more trichs, some say it doesn’t do shit :) i don’t have a big facility to do scientific tests, so i have no idea but my buds seems ok.
 
P

Pass2TheLeft

323
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To add to my previous post, co2 is only absorbed during the time the plant is receiving usable light. Reducing the usable light would likely reduce the amount of co2, nutes and water it could draw in to use during the night to grow. Reducing usable light is bad idea imo. I have heard of several techniques to trick a plant into producing more terps and thc such as the hot water shock, raising temp, or even buring hot coals near the root ball but I would just stick with full power 12/12 myself and maybe 48 hours of dark at the end.
The whole point of darkness is to stop the plant from uptaking nutes and fading the plant in darkness the plant uses its stored energy;) it also tells the plant its finished
 
JWM2

JWM2

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200DDDD3 7B50 446F 8068 163C366F5BC8
I’m actually experimenting with the Emerson effect. I added some far red leds to my quantum board setup and they come on the last few hours the lights are on and go off 15 minutes after the other lights shut off. I’m interested to see if it helps at all. Of course I have no control to compare it to, it’s just cheap enough to try and I’ve heard the results are better yield, quicker flowering times and better potency. Who knows though. We’ll see.
 
P

Pass2TheLeft

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View attachment 840727 I’m actually experimenting with the Emerson effect. I added some far red leds to my quantum board setup and they come on the last few hours the lights are on and go off 15 minutes after the other lights shut off. I’m interested to see if it helps at all. Of course I have no control to compare it to, it’s just cheap enough to try and I’ve heard the results are better yield, quicker flowering times and better potency. Who knows though. We’ll see.
Will be very interesting to see your results i suspect you dont really need a control group if you have done that strain a few times before bro
 
JWM2

JWM2

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Yeah I’m very familiar with the strains. So I’ll know either way. It uses so little electricity that unless something bad happens I’ll keep using them. The board was $37 on amazon.
 
MIMedGrower

MIMedGrower

17,190
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I have learned through trial and error with picky Thai/diesel strains to move the plants away from the lights a few inches during ripening. I use stands and the lights are fixed up high.

This reduces the intensity but nowhere near 50% like suggested in this thread.

Once I got dialed in and the plants have the edge taken off from intensity and radiant heat the amount of visible trichomes and potency went up.

This is with 600w hps lamps.

Flavor and smell went up too. :-)
 

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