logic behind photoacclimation?

JonCreighton

Well-Known Member
i get the process.. im just curios why this is done...

is this a plant health or yield kinda thing... or an energy principals kinda thing... ??

id assumed it was a plant heath kinda thing... but if u plant a seed in lets say june.. even as a seedling ur looking at like 1200 ppfd. its a dli of like 50+... and it doesnt seem to hurt the plant...

so that bring me back to thinking its an energy principals kinda thing... kinda like they can only absord 500 ppfd as a seedling so why run em at 1000 ppdf...

thanks
 

Macncheesehaze

Well-Known Member
If you were born in a cave With artificial light and spent your whole life without ever seeing the sun You’d get sunburnt walking outside. Same goes for a plant.
 

JonCreighton

Well-Known Member
im not talking about photo acclimating outside.. uv hardening
im talking about charts u see of how people run their lights... they tick up the DLI... for instacne... fluence starts their clones w a dli around 10... then they slowly increase their light intensity untill they get to a dli around 40... then flower at 12x12 bumping the dli back down to 30ish... then continue to slowly increase it to 45ish durring flower...

and its basivally the same on any light intesnity dli ppfd whatever chart i can find...

im just asking if someone can explain why this is done... i can pop a see outside in june w a dli around 50 and the seed seems fine.... so is the photoacclimation thing done because they will only absord a small amount of that light on a june day... so if im growing inside why push the lights at 800ppfd or somethiung if a 3 week onld plant can only absord around 500ppfd...

just educate me on why exactly the light strength is slowly ticked up.. im doing it... looks fine.. just curious behind the science or whatever
 

JonCreighton

Well-Known Member
and i been trying to figure this one out for a little while.... this guys all over the place... anyone got a theory on why hes bouncing all over the place durring flower
 

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xtsho

Well-Known Member
Damn. I've been growing for decades and have never even worried about any of this or needed any charts. If I have veg plants inside and it's nice and sunny outside sometimes I stick them outside and turn off my light. I've never had any issue. The only thing I'll acclimate is some vegetable starts in early spring.

I don't bother with PPFD, DLI or what fluence whatever that is does. It's a damn pot plant. Give it light, feed it, let it grow. Unless you're majoring in Plant Science and doing a study why bother worrying about this?
 

JonCreighton

Well-Known Member
Damn. I've been growing for decades and have never even worried about any of this or needed any charts. If I have veg plants inside and it's nice and sunny outside sometimes I stick them outside and turn off my light. I've never had any issue. The only thing I'll acclimate is some vegetable starts in early spring.

I don't bother with PPFD, DLI or what fluence whatever that is does. It's a damn pot plant. Give it light, feed it, let it grow. Unless you're majoring in Plant Science and doing a study why bother worrying about this?
i guess i would say im trying to figure this stuff out... i come from ther world of tomatoes... and it seems to me people in that world are more concerned w like the growing process... i mean in the end its jsut a tomatoe so i think its a hobby or passion for them...where here in the nugs space people just kinda want the best end product... both those are cool...

so becuase its kinda my hobby.. i like the science.. i like to find my way to implement the science.. i work in contruction so designing the room is kinda fun for me... i want to see how i can get x ammount of photons to the plants at the most efficent rate.. and id like to grow dispencary quality nugs at aorund 2g/w.. lol...

pretty much the only guy i listen to in this space is bruce bugbee... and he says to KNOW YOUR LIGHTS ITS THE MOST IMPIORTANT THING BY FAR!!!

problem is the lighting the most important thing was neglected for so long because we couldnt really manipluate it.. 50% 75% and 100% ballasts dont offer much for adjustment... but i think this is important I CANT FIND A SINGLE COMMERCIAL GROWER WILLING TO SHARE THEIR LIGHTING STRATEGY THAT IS NOT TICKING UP THEIR LIGHTS.. usually 5-10w a day...

so i guess id say im worried about it beacuse the best and smartest people in this industry are worried about it.... very worried about it.. infact one guy at umass told me light interval is number 1... then co2 qnd leaf temp blah blah blah...

if u want to learn about it.. look up the bruce bugbee videos online... dudes is the number 1 resource IMO
 

JonCreighton

Well-Known Member
so why u asked why bother?... i dont know that why im asking.... but every single professional IS BOTHERING... so there IS a reason... is it quality.. is it qauntity.. is it energy principals... id like to know so i can use that tool aswell...

if u havent kept up w the science of the last 5 years ur still running at like 40% photsythises btw... so id probable look into those things u say u dont look into... DLI, ppdf, leaf temp, co2, vpd...you could probable double your rate of photosythesis... i cant double the yield closing the system and focusin on those things... but i can get close
 
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JonCreighton

Well-Known Member
Damn. I've been growing for decades and have never even worried about any of this or needed any charts. If I have veg plants inside and it's nice and sunny outside sometimes I stick them outside and turn off my light. I've never had any issue. The only thing I'll acclimate is some vegetable starts in early spring.

I don't bother with PPFD, DLI or what fluence whatever that is does. It's a damn pot plant. Give it light, feed it, let it grow. Unless you're majoring in Plant Science and doing a study why bother worrying about this?
im talking about growing indoors at all times... i was using the outdoor example as a way to say im confused... i was saying why are all these professional outfits putting there seedlings under a dli of 10 inside and slowly rising it... when i can put a seedling outside under a dli of 50 and it doesnt seem to mind.. disregard the inside outside thing and just think about the ammount of photons thats falling on the plant... i was making an observation that if a seedling outside under a dli of 50+ doesnt seem to mind that mich light maybe the pros are doing this because its a finacial gram/w thing or an energy princals thing... and not a thats too much light for a seedling its gunna hurt it kinda thing...
 

BluntMoniker

Well-Known Member
If your concern is why they do it in commercial grows, the word "commercial" should answer the question... money.

More likely than not, they're adjust their lights up and down, so they are using the least amount of power (money) necessary to produce a top quality plant. No need to blast a 2 week old seedling with full strength lighting.
 

Bunnybrew

Well-Known Member
If your concern is why they do it in commercial grows, the word "commercial" should answer the question... money.

More likely than not, they're adjust their lights up and down, so they are using the least amount of power (money) necessary to produce a top quality plant. No need to blast a 2 week old seedling with full strength lighting.
Yaaaassssss
If your concern is why they do it in commercial grows, the word "commercial" should answer the question... money.

More likely than not, they're adjust their lights up and down, so they are using the least amount of power (money) necessary to produce a top quality plant. No need to blast a 2 week old seedling with full strength lighting.
You speaketh the truth my friend. Brethren. Hear brother blunt
 

JonCreighton

Well-Known Member
If your concern is why they do it in commercial grows, the word "commercial" should answer the question... money.

More likely than not, they're adjust their lights up and down, so they are using the least amount of power (money) necessary to produce a top quality plant. No need to blast a 2 week old seedling with full strength lighting.
ya i figured it was a financial thing.... but take a look at the graph i posted above w the guys kinda all over the place... theres a basic upward trend untill what he calls ripening (weeks 7-9ish) but it isnt a straight line.... why is he going up faster at some times and slower at other....so that leads me to believe there is maybe somthing else to it...

im tolf most large scale commercial grows do not move their lights.... i think they jsut do it via light density and light interval.... i do move my lights when i do it tho... im trying to save money on hvac so im doing everything i can to keep my leaf temp and room temp at 80 w the lights alone...
 

JonCreighton

Well-Known Member
If your concern is why they do it in commercial grows, the word "commercial" should answer the question... money.

More likely than not, they're adjust their lights up and down, so they are using the least amount of power (money) necessary to produce a top quality plant. No need to blast a 2 week old seedling with full strength lighting.
im not trying to be mean but when u say "more likely than no"t are u just theorizing... like me... or has someone who actually knows explained this to you...
 

JonCreighton

Well-Known Member
cuz if where just guessing ill give u guys mine....

try not to think about the clone and the outdoors i probable confused everyone w those analogies...

what fluence says is that w photoacclimation u can reach higher DLIs in flower than u could in veg maybe evern surpass levels you were at in veg.... so they are trying to push high light.... but they are saying push it safely 25-50mm a day everyday once u start flower... the first half of that comment is from sean sangsters youtube video "how lighting effects cannabis cultivation" and the second half of that is from fluences cannabis cultivatiomn guide... incase anyone wants to look closer at what im saying....

so clearly they are trying to oush light as high as they can.. but they still recomend increase ur ppfd by 25-50.... thats like 5 watts... if u had 1000 lights u might crack $1... so why arnt they increaseing by more than 25-50 say increase the ppfd by 100 daily if its an incredabily small cost difference... it has to be a plant health thing... financial thing doesnt add up
 

BluntMoniker

Well-Known Member
im not trying to be mean but when u say "more likely than no"t are u just theorizing... like me... or has someone who actually knows explained this to you...
I'm using critical thinking. The only 2 reasons to do it, would be to replicate the sun's intensity across a grow season in an effort to mimic the plants natural grow environment... or financial planning.

Out of those 2 options, which one sounds the most likely to be the case? It could be either/or depending on the grower, but its one of those 2 reasons, and more likely to be done for financial reasons than the other.
 

JonCreighton

Well-Known Member
I'm using critical thinking. The only 2 reasons to do it, would be to replicate the sun's intensity across a grow season in an effort to mimic the plants natural grow environment... or financial planning.

Out of those 2 options, which one sounds the most likely to be the case? It could be either/or depending on the grower, but its one of those 2 reasons, and more likely to be done for financial reasons than the other.
i agree.. financial reasons were my original thought.... but the more i think about it.... these guys are in week 3-4-5 of flower... this is where ur generating yield... this is when ur producing money... and they are still limiting the light way lower than they could... they could be pushing a ppfd of 1000 or 1500 striaght thru and generating huge yields... and there not... and the difference between upper limit they reccomend (adding 50 ppfd) and just going straight up to 1000 or 1500 is minimal... the difference between increasing ur ppfd by 50 is minimal...

IM SAYING THE DIFFERENCE BETWEEN INCREASING UR LIGHTS BY 50MM (what they reccomend) AND PUSHING THEM UP MUCH FASTER IS LIKE $5 A DAY.... SO IN PRIME TIME PRODUCTION THEY ARE LIMITING THEIR LIGHT NOT FOR FINANCIAL REASONS... the offset of pruction durring those times would outweigh the cost by 1000 times....

what i think is going on is they set a goal of ppfd to reach at either the climax or the end oif flower.... lets say flip to flower at a ppfd of 600... and they want to end at 1000ppfd.... they divide to difference and space it out over the flower schedule.... as u can see the cost between 600ppfd and 1000ppfd is minimall... but they are not jumping stright to 1000ppfd and pushing yield throughout flower...

im curious why u say more likley done for financial reasons... i had thoguht the same... but the math doesnt even come close to adding up...

jon
 

JonCreighton

Well-Known Member
I'm using critical thinking. The only 2 reasons to do it, would be to replicate the sun's intensity across a grow season in an effort to mimic the plants natural grow environment... or financial planning.

Out of those 2 options, which one sounds the most likely to be the case? It could be either/or depending on the grower, but its one of those 2 reasons, and more likely to be done for financial reasons than the other.
im not sure those are the only two reasons... neither of those replicate the sun over the course of a season... infact they are the opposite iof the sun durring growing season... light intensity slowly decreases throughout flower outside... DLI 60 july 50 august 40 september ect... outdoors flower w a dli slowly lowering... its why i put lights in my outdoor greenhouse and slowly increase them only durring flower... im trying to offset the light integral lowering thruout the season... so these flower schedules are opposite the sun it cant be that...

and like iv said i dont think its financial.... i can think of a lot of other reasons... mainly its a scientific thing to increase plant canabinoid production... or thats just how hard u can push them if u want good quality...

but look at the posted grapht.... he is raising his light at all different speeds.... this tells us the plants can handel slightly more than he is giving it sometimes.. and that he is targeting specific things.... and from what i can tell this is the most kinda indepth one i can find... and its from a guy who recently kinda left the industry i think... so this might be a this guy spilling the beans...

everything points to something complicated and important going on here... lets figure this out
 

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BluntMoniker

Well-Known Member
im not sure those are the only two reasons... neither of those replicate the sun over the course of a season... infact they are the opposite iof the sun durring growing season... light intensity slowly decreases throughout flower outside... DLI 60 july 50 august 40 september ect... outdoors flower w a dli slowly lowering... its why i put lights in my outdoor greenhouse and slowly increase them only durring flower... im trying to offset the light integral lowering thruout the season... so these flower schedules are opposite the sun it cant be that...

and like iv said i dont think its financial.... i can think of a lot of other reasons... mainly its a scientific thing to increase plant canabinoid production... or thats just how hard u can push them if u want good quality...

but look at the posted grapht.... he is raising his light at all different speeds.... this tells us the plants can handel slightly more than he is giving it sometimes.. and that he is targeting specific things.... and from what i can tell this is the most kinda indepth one i can find... and its from a guy who recently kinda left the industry i think... so this might be a this guy spilling the beans...

everything points to something complicated and important going on here... lets figure this out
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
 
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