logic behind photoacclimation?

youraveragehorticulturist

Well-Known Member
Remember that Daily Light Integral counts total light "received" in a day.

In addition to changing the DLI by changing the intensity of the lights, you can also change in by altering the length of your "days."

So if you give your clones 16-8 until they root, then 18-6 in early veg and finally 20-4 in late veg, you've raised your DLI over the course of veg.

Then, when you switch to 12-12 you decease the DLI because you've suddenly made the days shorter. Or reduced the time to receive light.

After the switch to flower it's natural to add more light or crank up the intensity, your plants are getting bigger. Finally, near the end you can dim the light to lower temps and slow the plant down to prevent foxtailing and fluffy buds.

Kind of unimportant, but where do you live that you can put a freshly popped seedling in full sunlight in mid June? Northern Siberia?
 

JonCreighton

Active Member
You said they lower light intensity towards the end of flower, then say they don't change the light intensity to match the sun, because the sun lowers in light intensity towards the end of the growing season.

Your talking yourself in circles. If you think its something other than the obvious things, and EVERYONE who has answered is incorrect in your eyes, then why do you keep asking the same question expecting a different answer?

Better yet, dont respond to this... tired of repeating myself. Hope you figure out whatever you think you need to
DUDE.. UR SO WRONG

take a second... like 1 second... and look at the graph i posted for u.... the DLI RASIES FOR 14 WEEKS AND LOWERS FOR 3 WEEKS.... WHAT SUN DOES THAT.... in almost any flowering season outdoors the DLI is decreasing.

i ask a question for the logic behind somethign.... u come in and give the obvious answer.... i try to show examples of how that answer doesnt add up... i figure by process of elimination we can figure this out... why dont we think about this a little deeper.....

YOU HAVENT ANSWERED ANYTHING.... BUT IF U THINK U HAVE... HOW DOES UR THEORY RECONCILE WEEKS 7-10?????????????
 

JonCreighton

Active Member
Remember that Daily Light Integral counts total light "received" in a day.

In addition to changing the DLI by changing the intensity of the lights, you can also change in by altering the length of your "days."

So if you give your clones 16-8 until they root, then 18-6 in early veg and finally 20-4 in late veg, you've raised your DLI over the course of veg.

Then, when you switch to 12-12 you decease the DLI because you've suddenly made the days shorter. Or reduced the time to receive light.

After the switch to flower it's natural to add more light or crank up the intensity, your plants are getting bigger. Finally, near the end you can dim the light to lower temps and slow the plant down to prevent foxtailing and fluffy buds.

Kind of unimportant, but where do you live that you can put a freshly popped seedling in full sunlight in mid June? Northern Siberia?
ya i hear ya with the photo period.... ill do that up to like an hour difference... if im having a hard time getting the PPFD i want at a specific leaf temp... ill just get the ppfd and leaf temp where i want it and adjust DLI w photoperiod a little...

everyone seems to keep their lights at the same strength when they flip... thats the persipitus drop in all the charts at the start of flower.. just a photoperiod thing im sure of that.... but then i think its a combo of lowering lights and adjusting wattage to achieve what they want.... looking at the evidence im about to draw the conclusion that most pros have come to thge conclusion u can only rasie ur ppfd by around 50ppfd a day without damaging the plant... but i still think theres more to this... if i had to guess i dont know how to describe it but some kind of energy production ratio maximising at the point when cannabinoids are the focus of the plant or maximising durring peak cannabinoid production... if u look at weeks 7-10 on the graph i posted theres like a faster and slower increase speeds... then even a drop in DL"I durring flower followed by another rise.... just weird...

massachusetts.... i go later than most cuz i cant have 10ft ers... straight up mid summer... doesnt seem to be a problem... most charts show a DLI are 60... once we start getting into flower ur DLI goes way down... around 35 right now... showrt days and weaker light... once we hit flower ill start ticking up the lights to try and keep the DLI 50+ if possible
 

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BluntMoniker

Well-Known Member
DUDE.. UR SO WRONG

take a second... like 1 second... and look at the graph i posted for u.... the DLI RASIES FOR 14 WEEKS AND LOWERS FOR 3 WEEKS.... WHAT SUN DOES THAT.... in almost any flowering season outdoors the DLI is decreasing.

i ask a question for the logic behind somethign.... u come in and give the obvious answer.... i try to show examples of how that answer doesnt add up... i figure by process of elimination we can figure this out... why dont we think about this a little deeper.....

YOU HAVENT ANSWERED ANYTHING.... BUT IF U THINK U HAVE... HOW DOES UR THEORY RECONCILE WEEKS 7-10?????????????
Did you really quote me after I asked you not to? What a jebroni

Sun moves, light intensity/angle of the sun changes, DLI/ppfd reaching plant changes (lowers) accordingly... you said this yourself. Of course, the suns grow season is longer, but thats where the "money" comes in... they want max yield so they give it higher ppfd values for longer in flower even with reduced lighting times, and then drop them when they are unnecessary. Again, matching the sun, and money. Think in terms of bro science, not fucking helioseismology and the answer becomes clear

Now... IF THAT DOESNT ANSWER YOUR QUESTION AND YOU NEED TO USE CAPITAL LETTERS AF IF THAT CHANGES ANYTHING, PLEASE STOP QUOTING ME LIKE I ASKED YOU TO ORIGINALLY, AND JUST GROW YOUR PLANTS HOWEVER THE FUCK YOU WANT TO... jebroni
 
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JonCreighton

Active Member
Did you really quote me after I asked you not to? What a jebroni

Sun moves, light intensity/angle of the sun changes, DLI/ppfd reaching plant changes (lowers) accordingly... you said this yourself. Of course, the suns grow season is longer, but thats where the "money" comes in... they want max yield so they give it higher ppfd values for longer in flower even with reduced lighting times, and then drop them when they are unnecessary. Again, matching the sun, and money. Think in terms of bro science, not fucking helioseismology and the answer becomes clear

Now... IF THAT DOESNT ANSWER YOUR QUESTION AND YOU NEED TO USE CAPITAL LETTERS AF IF THAT CHANGES ANYTHING, PLEASE STOP QUOTING ME LIKE I ASKED YOU TO ORIGINALLY, AND JUST GROW YOUR PLANTS HOWEVER THE FUCK YOU WANT TO... jebroni
alright dude... maybe we got off on the wrong foot... I can come at people online and thats not my intention... understand I didn't mean that.. or I probable felt a little bad about it later...

ok that being said... im not saying ur wrong and im moving a little to a different topic but it will help me understand....

im talking all indoors... growing under LEDs... w a light sensor...

do u know why... in the graph I posted above.... what is with the drop in DLI in prime flower time.... im talking week 10-11 he actually reduces his DLI... then he raises it for another two weeks till week 13.... then he starts dropping for good until its harvest...

it just leads me to believe there are times during the growth cycles where the plant is focused on THC and less on growth and cultivars ar trying to maximize that... that maybe the goal is baseline for the majority of the grow cycles but during 2 or 3 critical times for THC or CBD or whatever you want to be at 120% of baseline.

thats just a theory and open to debunking...
 

JonCreighton

Active Member
Overthinking things.
im not sure thats the case... were just getting a lot of the data now... a lot of BS has been and is going to be debunked... a lot of of stuff changing in this industry... feels like science has finally arrived in this space
 

JonCreighton

Active Member
Where are you getting these lighting charts from?

Do they not provide any other information?
ya I was trying to bring up the fluence charts but I couldn't on this comp for some reason.... look up fluency cannabis cultivation guide... and listen to Sean sangsters YouTube video on cannabis lighting... I think I posted the video above in another post... there's a page early in the cannabis guide thats all about lighting.... according to the migrow YouTube channel Fluency spiders something or other light is at the top of his chart... so these guys understand lighting this isn't so hack company I don't think...

now they reccomened like a stable increase in lighting... id still like to know why they recommend pushing them only +50ppfd a day... I mean this is a lighting company they have every reason to want to sell more lights...

the chart I posted above if from this article

what-to-know-about-lighting-cannabis-from-a-former-greenhouse-cultivator

what's interesting is I looked up this higginbotham guy who wrote the article above... and I think im not sure but I think he had Sean sangsters job before Sean Sangster... I think this higginbotham guy ran fluence year or two ago. so im getting all conspiracy on you guys and thinking that fluency is giving us some of the information... I mean its their business to consult I think I can't see giving up all the secrets... but maybe this higginbotham guy is telling tales outside of school... maybe they figured out the plant growth cycles and are pinpointing specific things for specific reasons... THC production.. CBD production... whatever... I just can't rationalize why higginbotham is bouncing his DLI around all over the place.. going up faster and slower at different time... even reducing his DLI for a week or two during flower then going back up lol.... I mean what's up w this...
 

xtsho

Well-Known Member
im not sure thats the case... were just getting a lot of the data now... a lot of BS has been and is going to be debunked... a lot of of stuff changing in this industry... feels like science has finally arrived in this space
Yes overthinking. No need to watch youtube videos and study charts. Give the plants light and call it a day.
 

youraveragehorticulturist

Well-Known Member
ya I was trying to bring up the fluence charts but I couldn't on this comp for some reason.... look up fluency cannabis cultivation guide... and listen to Sean sangsters YouTube video on cannabis lighting... I think I posted the video above in another post... there's a page early in the cannabis guide thats all about lighting.... according to the migrow YouTube channel Fluency spiders something or other light is at the top of his chart... so these guys understand lighting this isn't so hack company I don't think...

now they reccomened like a stable increase in lighting... id still like to know why they recommend pushing them only +50ppfd a day... I mean this is a lighting company they have every reason to want to sell more lights...

the chart I posted above if from this article

what-to-know-about-lighting-cannabis-from-a-former-greenhouse-cultivator

what's interesting is I looked up this higginbotham guy who wrote the article above... and I think im not sure but I think he had Sean sangsters job before Sean Sangster... I think this higginbotham guy ran fluence year or two ago. so im getting all conspiracy on you guys and thinking that fluency is giving us some of the information... I mean its their business to consult I think I can't see giving up all the secrets... but maybe this higginbotham guy is telling tales outside of school... maybe they figured out the plant growth cycles and are pinpointing specific things for specific reasons... THC production.. CBD production... whatever... I just can't rationalize why higginbotham is bouncing his DLI around all over the place.. going up faster and slower at different time... even reducing his DLI for a week or two during flower then going back up lol.... I mean what's up w this...
The article you linked mentioned supplementing CO2, and how the plants can use more light as CO2 concentrations rise. In the article they talk about going from 700-1200 ppm over the course of the grow. It sounds like they are increasing the brightness/intensity of the lights as they raise CO2.

So, long story short, it's about money. Or using optimal levels of CO2 and light, adjusting gradually along the way, never using too much and wasting it.
 

JonCreighton

Active Member
The article you linked mentioned supplementing CO2, and how the plants can use more light as CO2 concentrations rise. In the article they talk about going from 700-1200 ppm over the course of the grow. It sounds like they are increasing the brightness/intensity of the lights as they raise CO2.

So, long story short, it's about money. Or using optimal levels of CO2 and light, adjusting gradually along the way, never using too much and wasting it.
its the light driving the co2.... you adjust your co2 ppm based on lights and leaf temp... i cant image any reason to make co2 intentionally your liming factor.... the co2 is going to tell you at what photosythic rate the plants will be turning over the photons from the lights... so your light intensity is your light intensity and your limiting factors emerge your photosythic rate...

its not a limting factor thing you can run up toward high rates of photosythesis the whole grow if ur clicking right... you wouldnt run your light at 800ppfd w a 50% photsythetic rate and achieve a net photosythisis of 400... when you could just run the lights 400ppfd...

i think i got the photoacclimation logic down... concensus around the industry seems to be rasie the lights by 25-100ppfd a day..

im more curious why the higginbotham guy is lowering his DLI for a few weeks... and raising his lights at differnt speed durring flower.... whats the logic behind his program... u can see in the graphs fluence does ur basic tick upward.. pretty self explainitory.... but whats w higginbothams roller coaster program... if hes saving money in places... hes highlighting other places... why save money in some places and push the plants harder at other places.... im wonndering why he is doing these things at those specific times... and im not talking about the drop when he flipped to flower... im talking about just the 9 weeks of flower
 

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ComfortCreator

Well-Known Member
He would tell you every 3 to 4 weeks they can handle another 5DLI or so. There is a recommended maximum it reaches while still growing flowers. Then it can be increased a bit more for ripening before trailing off for the finish.

Is DLI identical for every strain? No...so the curve is what then exactly? A guide. There is no magic in those numbers its a pretty smooth graph.
 

JonCreighton

Active Member
He would tell you every 3 to 4 weeks they can handle another 5DLI or so. There is a recommended maximum it reaches while still growing flowers. Then it can be increased a bit more for ripening before trailing off for the finish.

Is DLI identical for every strain? No...so the curve is what then exactly? A guide. There is no magic in those numbers its a pretty smooth graph.
got ya.... Thank you
 

JonCreighton

Active Member
He would tell you every 3 to 4 weeks they can handle another 5DLI or so. There is a recommended maximum it reaches while still growing flowers. Then it can be increased a bit more for ripening before trailing off for the finish.

Is DLI identical for every strain? No...so the curve is what then exactly? A guide. There is no magic in those numbers its a pretty smooth graph.
can i ask you another question.... so when a guy like bruce bugbee says u can run DLIs up to 60... you would need to achieve that DLI in veg first?? is that right?... that seems like a huuuuuge plant.... or do you think hes advocating a faster daily ppfd increase durring flower
 

JonCreighton

Active Member
Young plants have much less storagesites for the photosynthetic products, and indoors alot of potential is wasted when the lower leaves get no light and basically dont do much...
correct me if im wrong this is how i interpret it... DLI a plant based measurement.... like once the LEDs came out we realised theres a million different ways to get the plants the light they need... so DLI came out as kinda a wy to measure that.. as opposed to ppfd par lux which are light measurements.. so this graph is kinda the goal from a plants perspective... so biomass wouldnt figure in horizontally speaking... i dont want to put words in your mouth but are you saying im thinking of this in terms of 1 dimension (horizontal) and there's a 2 dimensional thing to consider (horizontal tal and verticle)?... Thats cool
 
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ComfortCreator

Well-Known Member
correct me if im wrong this is how i interpret it... DLI a plant based measurement.... like once the LEDs came out we realised theres a million different ways to get the plants the light they need... so DLI came out as kinda a wy to measure that.. as opposed to ppfd par lux which are light measurements.. so this graph is kinda the goal from a plants perspective... so biomass wouldnt figure in horizontally speaking... i dont want to put words in your mouth but are you saying im thinking of this in terms of 1 dimension (horizontal) and there's a 2 dimensional thing to consider (horizontal tal and verticle)?... Thats cool
DLI is a time based interval, the other measurements are not based upon time. So your ppfd may be 1000...but for how long? DLI tells you.
 

Kassiopeija

Well-Known Member
So your ppfd may be 1000...but for how long?
until it hits the top leaf canopy, the rest of the plant gets only a tiny chunk of the energy. If the lighted out plants are only lettuce - it won't matter, but 1.50m tall cannabis plants? This circumstance seems to be neglected/omitted by DLI and I have the feeling this is something Jon may have thought about....?
 
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