Daily Light Integral DLI Relation To Cannabis Yield

Daily Light Integral (DLI) Relation To Cannabis Yield
Professor DeBacco
Daily Light Integral (DLI)
Daily Light Integral (DLI) describes the number of photosynthetically active photons (in the 400-700 nm or PAR range) that are delivered to a specific area over a 24-hour period.
For outdoor locations this will be season and weather dependent
For indoor locations it can more easily be calculated by simply knowing the lights output and hours on.
Calculating DLI
DLI is the sum of the per second PPFD measurements during a 24-hour period.
If the photosynthetic light intensity remains constant (as with artificial lighting units) for a defined time period (duration) then the DLI can be calculated.
Outdoor locations are more complicated and require more data collection over a period of time.
However, the end result is the same.
PPFD Rating Over Six Hours
PPFD in µmol/(m2sec)
Range is 0-2000 (no light to full sun light)
But remember that sunlight is subject to continual variability due to clouds.
For artificial lighting 510 µmol/(m2sec) should be considered the absolute minimum
PPFD vs DLI
PPFD = rate of photos per second
How fast is it raining per second?
DLI = sum of photons in a day
How much did it rain in a day? (What is the total?)
DLI Related to Stage of Cannabis
Target DLI can vary with stage of plant development.
However, if a grower is able to keep all other plant requirements at optimum the DLI can be increased above these suggested levels to maximize production
DLI Outdoor Perspective
Note on a summer full sun days DLI can reach 60 mol/m2/day
The image shows the amount of light received across the United States each month.
During fall and winter latitude has a strong influence of DLI
Converting 1000 µmol/(m2sec) for 20hr. to DLI
A plant receiving 1000 µmol/(m2sec) for 20 hours will have a DLI of how much?
Answer = 72 moles / (m2*day)
See calculations below…
Converting 1000 µmol/(m2sec) for 12hr. to DLI
A plant receiving 1000 µmol/(m2s) for 12 hours will have a DLI of how much?
Answer = 43.2 moles / (m2*day)
See calculations below…
Light Intensity Related to Cannabis Production
At a certain point in order for plants to take advantage of higher intensity lights, there needs to be CO2 supplementation
If light is increased beyond this amount the CO2 becomes the limiting factor and plants will not be able to use the extra light levels making it a waste to produce.
The Threshold for optimal growth and photosynthesis is a DLI of 65 moles per day.
Light Intensity During Veg Cannabis Phase
Since Vegetative phase can have some variability due to grower duration of light to dark the maximums are provided
Notice that if you have lights that produce less intensity they need to be run for a longer duration.
*While this is possible in Veg, the light duration is fix in flower
Light/dark schedule and PPFD recommendation without CO2 enrichment
24/0 schedule: 752.31 µmol/(m2sec) for a DLI of 65 moles / (m2*day)
18/6 schedule: 900 µmol/(m2sec) for a DLI of 58 moles / (m2*day)
Flower photoperiod comparison 12/12 schedule: 900 µmol/(m2sec) for a DLI of 39 moles / (m2*day)
Light/dark schedule and PPFD recommendation with CO2 enrichment
To reach a DLI of about 65 moles / (m2*day)…
24/0 schedule: 752 µmol/(m2sec)
18/6 schedule: 1003 µmol/(m2sec)
Flower photoperiod for comparison 12/12 schedule: 1505 µmol/(m2sec)
Light Intensity During Flowering Phase of Cannabis Production
Since the flowering phase is defined as only 12hours of continuous light the duration of light remains the same.
What is variable is the intensity which will directly impact the DLI
Minimum Level
PPFD of at least 510 µmol/(m2sec)
Optimum Range without CO2 Enrichment
PPFD of 800-1000 µmol/(m2sec)
*Without CO2 max intensity that plants can use is no higher than 900 µmol/(m2sec)
Optimum Range with CO2 Enrichment
PPFD of 1000-1500+ µmol/(m2sec)
Does not seem to be a saturation point even up to 1800 µmol/(m2sec)
Special Thanks To…
Combination of research data from…
Dr. Bruce Bugbee of Utah State University and Founder of Apogee Instruments Inc.
Shane Torpey MICRO founder
Professor Erik Runkle of Michigan State University
Link to Lecture Slides: drive.google.com/file/d/1LCG4...
*Due to the description character limit the full work cited for "Daily Light Integral DLI Relation To Cannabis Yield" can be viewed at... drive.google.com/file/d/1ygpD...

[@timjim7830]

I love how your channel is dry, straight-to-the-point scientific, and 100% cringe-free. No trashy trap music and getting all stoned, forgetting what you're talking about mid-sentence. We need more people who treat the craft with the respect it deserves. Well done!

[@DeBaccoUniversity]

Thanks for this comment and great to know you like the format!

[@dub537h5]

Getting stoned is the point of the video, bro!

[@Pazuzu1500]

Thank you for providing clear and concise information without your own mix tape in the video. I really appreciate you doing these videos.

[@DeBaccoUniversity]

Glad it was helpful and thanks for taking the time to provide this comment!

[@gardin9346]

Another good video from Prof Debacco, Glad to see you using data from Dr Bruce Bugbee his work is good. he has done so much in his field of Plant physiology.

[@DeBaccoUniversity]

Goal is to provide a collection of researchers to help growers better understand the data that is out there so they can best apply it to their individual situations.

[@telescopehorizon]

I think watching every one of your videos should be a prerequisite before growing.

[@DeBaccoUniversity]

Thanks for this, and those who have watch the videos have reported improvements to their growing which is great to know! Be sure to share the channel with others!

[@nicholastrascik705]

You have soooo much useful information I'm trying to share it as best I can

[@DeBaccoUniversity]

Your effort is very much appreciated!

[@Rad631]

Amazing and compact information in one single video. So valuable, thank you so much! Now I'm more secure about making decisions when it comes to light choosing and how to manage the saturation of CO2. Cheers!

[@DeBaccoUniversity]

Great to know, thanks for commenting! There are hours of research to ensure the content is delivered quickly and to the point without getting people lost and not shorting information. This balance is a challenge so it is always notice to know when others (like yourself) take the time to comment and confirm this original plan for the videos on this channel.

[@chrisgomez3449]

Thank you for all the I'm knowledge and research you provide us with keep up the good work and you're the real deal

[@DeBaccoUniversity]

You are welcome and be sure to share the content provided here on DeBacco University with others so they can also benefit.

[@sparkysmalarkey]

This video answered a question I posted in a different one, thanks for the content.

[@DeBaccoUniversity]

Glad you found the answer you needed here on DeBacco University!

[@zumbaladin]

Thanks for sharing that precious knowledge, will make good use of it!

[@DeBaccoUniversity]

Go forth and do good things!

[@c.j.mackay4032]

So it’s 3:13am and I’ve been watching your videos for HOURS! Lol. I’ve watched quite a few from Dr. BB and Shane from MIGRO so I have a basic understanding of what you’re talking about and the terms you’re using, but for the first time I think I might actually understand what I need to do to calculate my own. Of course it’s not happening at 3 in the morning haha but I’m actually kind of excited to sit down and do math tomorrow! I never thought I’d say that in my life. I’m very keen on optimizing (and really learning in a hands on way about) my indoor environment. My lights are made by Atreum, I think MIGRO was one of the few channels that reviewed them but there otherwise isn’t much information available online about them and nothing detailed. So I’ve got to figure it out myself. This video series here will be so helpful as I sit down with a pen and paper and figure out one number at a time and do the equations. I know the result will be better photosynthesis and faster growth which is why it will be worth all the effort :) math was never my strong subject.

[@DeBaccoUniversity]

Great quote... "for the first time I think I might actually understand what I need to do" This is the goal of the channel, quality and usable education!

[@NinjaRastaMon]

Hey you can just google a DLI calculator online, photon has one and a par meter app as well which helps. 800 par for 12hr is 34 DLI and 1000 is 43, 500 par for 18 hours is 32, 600 is 38...

[@618grow]

environment is everything imo..lots of airflow and having the light dialed in

[@kingcola3849]

Just found a great DLI calculator just add your par# and light hours and boom it's that easy it's called scynce led.

[@ricksimpson5788]

Q

[@zoltontheguitar]

Sir! This was a fantastic video! Thank you for this information. It was very helpful in understanding my lights better.

[@DeBaccoUniversity]

Thanks for the comment and subscription, be sure to encourage others to do the same!

[@lavarball3070]

awesome calculus and growing two of my favorite things!

[@DeBaccoUniversity]

Glad to combine your two favorite things... this just saves time;-)

[@ChadAF_YT]

They actually go hand in hand when you get into vpd/ppfd/dli you can get really measured in your approach to growing which helps in setting markers which can be used to test hypothesis against control groups. It can be as simple as defoliating one plant and not the others, to getting into charts and pinning yarn between them hypothesizing which variable attributed to the growth you tracked.

[@ChadAF_YT]

If you don’t end up in a tin foil hat talking about the stars, you still have more math/physics to study

[@HappyPappy_420]

Another great video sir, thank you

[@DeBaccoUniversity]

Nice to know the quality and content are still top tier!

[@ChadAF_YT]

I really enjoy your videos! Thank you for putting this information out

[@DeBaccoUniversity]

Thanks for watching and glad you like them!

[@marcelqueiroz8613]

Thank you very much! ✌🏼

[@DeBaccoUniversity]

You are welcome!

[@cv9672]

Hi Prof. Debacco, recently found you and i am very much enjoying your content! Keep up the excellent work i'll be recommending your channel to friends :)

[@DeBaccoUniversity]

Thanks for commenting and special thanks for helping to share the channel with others!

[@nicholastrascik705]

Thank you

[@DeBaccoUniversity]

You are welcome!

[@tiagobraga5206]

Thanks for the video

[@DeBaccoUniversity]

Thanks for your continued viewing of the content!

[@hamahamamies]

great video

[@DeBaccoUniversity]

Glad you enjoyed it.

[@navazoff]

merci pour votre partage de savoir

[@DeBaccoUniversity]

Je vous en prie!

[@clorca100]

That's a very interesting video man!!

[@DeBaccoUniversity]

Glad you found DLI interesting, hopefully you feel the same for other videos on the channel.

[@clorca100]

@@DeBaccoUniversity I do thanks for your work. At the market are affordable sensors for measuring dli? I have seen trolmaster agro have a par sensor suitable for greenhouses with supplemental light to achieve the par needs of the crop but this dli data gives you play on veg phase. In flower state you are limited to 12/12 cicle, you can play with 13/11

[@DeBaccoUniversity]

Yo may find this fact sheet helpful... www.extension.purdue.edu/extmedia/ho/ho-238-w.pdf

[@dang1099]

Hello, I just want to let you know that Shane is actually founder of MIGRO, with a G, not a C. I didnt know if you were aware or it was just an accident. Either way just want to leave a friendly comment letting you know. Cheers.

[@DeBaccoUniversity]

Thanks for pointing this out.

[@michaelbogdovitz9479]

Thanks

[@DeBaccoUniversity]

Welcome!

[@bigal8986]

Thanks for another great video! I have a question, if my 5 x 5 grow tent is in a much larger lung room and I'm pumping that rooms normoxic air 24/7 doesn't that replenish the CO2 to keep it a a natural level if the tent isn't overloaded with plants?

[@DeBaccoUniversity]

Ideally yes, but a meter is the only way to know for sure.

[@Magpyro]

Shout out Shane Torpey of Migro! He does great informative videos to help understand lighting.

[@DeBaccoUniversity]

He sure does!

[@willferridrums]

when you talk about enriching with C02, how much ppm are you talking about? I have one of those “Exhale” bags of fungus that is supposed to give off C02, but i’m not really sure if it is a significant amount for me to increase my light intensity.

[@DeBaccoUniversity]

Search the channel for "Carbon dioxide" and you will find many videos on the topic, but here is one to get you started.... kzbin.info/www/bejne/Zquoc595jah5gpI

[@quirin5061]

what would be optimal for a autoflower in flower?

[@Top_Gnana]

Great information! Thanks so much for sharing 🙏🏻 One question tho, is the rate of photosynthesis dependent upon temps under co2 enrichment. If so what temps are optimum? Thanks again 🙏🏻

[@DeBaccoUniversity]

Typically 86F optimum and under CO2 it could be up to 90F assuming proper environment including humidity.

[@BigFarm_ah365]

Was an optimal CO2 level mentioned in correlation to potential ppfd levels. I'm getting into 11-1300ppfd range and figured it was a good time to fully depress the accelerator as far as CO2 goes. I set it to 1300ppm. Is 1500ppm still considered highest optimal CO2 level?

[@DeBaccoUniversity]

Typical CO2 target level is 1200ppm as this is the main economic threshold. 1500ppm is still considered to be the maximum value (assuming no other factors are limiting) if return on investment is not the main focus.

[@NinjaRastaMon]

I finally made it to this level of realising about this factor using 12-1 and uncommon flower light tapering. Mostly no information about the level curve and why use high levels and when. Luckily using a 12-1 like I was pushing the veg, and then cutting down to 10 hr days, seemed to unknowingly do the trick for me, vs maintaining the same DLI from veg to par as 18-6 and 12-12 growers typically do. My guess is maintaining a better par into flower and tapering off for the intended last week or two would keep speed above natures curve but allow all the resins and oils to maintain . My question with shorter flowering days is can you raise the ppfd to 1250 for an 8 hour day without co2, vs 8-1000 ppfd for a 12 hour day?

[@DeBaccoUniversity]

Yes you can increase the light intensity just be sure to harden off the plants to reduce the chance of leaf burn.

[@NinjaRastaMon]

@@DeBaccoUniversity Thank you Mr. DeBacco, so far so good. Heading up to 950 soon for 10.5 hr days.

[@TheOO23]

Hey Professor ! Im a confused : on the "crop stage" chart max DLI is 45 , then on "DLI" chart you say 65 max while the values stop before 60. So what is max DLI for veg and flower with and w/o CO2 ? Also dropping DLI by 40% when switching from veg to flower seems counter-intuitive, it is not like that in nature; At that point plants grow fast, that is the beginning of the so called stretch period, so reducing light is strange. Do you have more info and sources on handling DLI when switching ? Thank a lot for your work !

[@DeBaccoUniversity]

Please see 8:06 and 9:39 for your answers.

[@agendreygrec3695]

If outgrown plant can manage a DLI of 60 outside with natural co2, why it would not be able indoor and oblige us to not exceed 900umol ? To reach 60 you need to 1389umol PPFD on a 12/12 cycle. Is there less co2 in an indoor cultivation than outdoor ? Thanks! Very useful!

[@agendreygrec3695]

I'm speaking all without co2 supplementation

[@DeBaccoUniversity]

Typically is not an economic advantage for indoor when you are paying for the energy to generate the light.

[@megigr0w111]

Really nice videos! Very informative and most importantly, scientific! I'm trying to get past the 1000ppfd.. LED lighting, temp and humidity are in range, Co2 @ 1500, but I never seem to be able to go over 1000ppdf. Even in veg, have to go at 400-450PAR and at the end of the 18hours, leaves are dropping like they have enough for the day. I'm puzzled! If you have any clue, that would be awesome! Thank you again!!

[@DeBaccoUniversity]

Make sure you are also monitoring the VPD.... kzbin.info/www/bejne/en24dJd4f9B9bM0

[@joshbeck289]

My plants seem too have had anuf light at around 14 hrs they start too droop a little more in the new growth everything is in check im only at 450 ppfd

[@kingcola3849]

Thank you doc your knowledge is a gift and I've watched dr.bb,Shane from my grow and others but I didn't get it until now.

[@DeBaccoUniversity]

Glad to help your learning process.

[@tonyhoward9268]

Where are those light measurements taken, the very top ,the middle or the bottom of the plant? I never hear anyone put emphasis on where to take the light reading. I have plants that are short and bushy and taking the reading at the very top makes sense because of how uniform everything is especially after lollipopping while I have a couple of strains that the tops have really stretched and there is a much greater distance from the tops and the rest of the plant giving a much bigger light variation from top to bottom.

[@DeBaccoUniversity]

Plant canopy height which is typically the upper plant portions.

[@618grow]

ok I'm in a 3x3 tent and currently in the seedling stage with PAR set at 250..is this low or spot on? ideal PAR for veg? 20 on 4 off

[@DeBaccoUniversity]

That should work out well for the plants.

[@Rizik1986]

Awesome data! I have a question if i may ask. I posted a video just a few minutes ago asking this question but i will ask here to see if you can shed some light : ) on my inquiry. I have a full spectrum led light. i have both the veg an bloom on 100%. I used an app called Photone and it shows my light temperature is 12,000k. I understand there is a difference between the color spectrum and the color temperature. For a seedling or a plant in Veg, is there any harm to come from running at 12,000k?

[@DeBaccoUniversity]

You also have to take PAR into consideration. 12,000K seems to be a bit outside of the normal color temperature so it will be interesting to see your results.

[@Rizik1986]

@@DeBaccoUniversity Par/PPFD is around 240 and DLI is around 14.5. I think I'm within range for a seedling. So far its growing very short. Very little distance between nodes. 3rd set of true leaves are forming. Its vibrant green. No obvious deficiencies. Everything seems great as far as I can tell. I might keep the lights on full spectrum the entire grow since I know the blue and red are both on full power. Interesting to see how it goes.

[@veela420]

The first picture is also the answer to the question of whether you should plant an outdoor plant in a spot that has before noon or afternoon sun if these are your only options. The answer is afternoon sun

[@DeBaccoUniversity]

Sometimes the answer is right in front of you;-)

[@dr.trichome6419]

👌👨‍🔬

[@DeBaccoUniversity]

Great to know it meets your approval!

[@DJTechnoboom]

This is just intensity of light on the the plant, what about the light spectrum ? can that effect how many hour's of light? or only effect production?

[@DeBaccoUniversity]

This DeBacco University should prove helpful for you... kzbin.info/www/bejne/q56QZHuQjauhmZY

[@Walter4Skin]

Great video thanks. Interesting the recommendation of up to 45 DLI in veg WITHOUT CO2. I've gotten light stress/burnt tips etc. at a DLI of about 30 in veg running 18/6... Is the recommended 45 DLI dependent on all other factors being spot on i.e. VPD, nutrition etc? In other words, how can we push to 45 DLI if plants are stressed at 30?

[@TnDAtkinson]

You likely have a few factors out of range for growing at 45 DLI. It could be the ph is a little off (should be 6-7ph), improper nutrient levels, watering cycle, medium, environment etc. All those things need to be fairly spot on for optimal growth. Trial and error are the only way you'll get it right. Take notes, write down what you do and when so you can keep track of results.

[@DeBaccoUniversity]

Try a 20/4 cycle to reach the proper DLI.

[@lp6132]

Ive got a lumatek zeus pro 600w led ( known as the photontek x 600w pro in the us and canada ) It gives out a PPF of 1620 µmol/s at full power. It comes with dimmable adapter and was wondering what sort of output i should be looking for at different stages of growth. I don’t see the point in amping up my electric bill by having the lights at full 600w power throughout seedling and veg stage if it doesn’t need it. What would you recommend through different stages of the grow. It has 25%, 50%, 75% and 100% adjustments. Any feedback would be much appreciated 👍🏼

[@DeBaccoUniversity]

The % do not mean much, you want to measure what your plants are getting in PAR at plant height. In short flower should have the highest PAR readings.

[@618grow]

Lux meter on Amazon $30...take reading and divide by 3.05 for PAR

[@olgaolga3292]

Dear Professor. What is your advice for clones?24/0 or 18/6?

[@DeBaccoUniversity]

18/6 or 20/4

[@OrdinaryAverageMan]

Have you measured the sunlight with a quantum par meter on a clear sunny day, on mine it reads around 1400/1500 ppfd not 2000

[@DeBaccoUniversity]

I get at least 1800+ on a bright sunny day at the plant canopy.

[@ClearWater7.62]

My light manufacturer suggest to keep the light at 24" between the canopy. But i see videos with lights that are hung 5' up? I'm confused. The par reading would be at 10?

[@DeBaccoUniversity]

Depends on the light and overall PAR (and heat) production. Start at the manufacture recommendation and make adjustments from there.

[@ClearWater7.62]

@@DeBaccoUniversity thanks for the reply 👍🏼👍🏼

[@David-we3sb]

Can I start giving my plants that just sprouted 60 DLI (~925 PPFD at 18/6 cycle)? or should I wait some time before giving 60 DLI to small plants? thanks

[@DeBaccoUniversity]

Depends how you treat them, think of this.... a newly emerged seedling in the field has to immediately deal with full sun.

[@618grow]

seems abit high

[@8ending8ranches]

People need to make cut and dry videos on dli

[@DeBaccoUniversity]

Hope this fits that category.

[@ahfint]

Hi, are there any studies about flowering with a photoperiod of 13/11?

[@DeBaccoUniversity]

This is likely possible, but you are playing with the line of veg and flower.

[@streetfighter0177]

Do you think the new studies with far red 700nm-800nm will change this chart in relation to photosynthesis?

[@DeBaccoUniversity]

More research will be needed as to the overall use/impact on the plant, but the early research is in support of the expansion of the Ps wavelength range inclusion... www.frontiersin.org/articles/10.3389/fpls.2021.693445/full

[@streetfighter0177]

@@DeBaccoUniversity Thank you, I do appreciate your time and effort!!

[@historyandhorseplaying7374]

Hello, could you please a video like this for tobacco growth? Or perhaps you already have

[@DeBaccoUniversity]

This is independent of plant type as it pertains to light intensity and duration per day. Calculate this and then relate it to all plants growing in this area.

[@historyandhorseplaying7374]

@@DeBaccoUniversity Thank you for responding! Sorry, I should have mentioned that I was referring specifically to the "DLI to cannabis yield" curve-- is that the same for all plants, or specifically cannabis? Would tobacco have a different curve? Am curious because am a newbie hobby tobacco grower for historical curiosity, not profit or anything. I'm getting the impression that most plants, as seedlings, have less stringent requirements than tobacco and cannabis, in that the latter require high color temperature and DLI compared to, say, tomatoes. But I think cannabis has completely different light requirements as an adult than tobacco? That is, tobacco can be grown outdoors in such relatively low light areas as Pennsylvania and West Virginia, whereas cannabis would never be productive outdoors in those environments? Or maybe I'm totally wrong.

[@davehansen4208]

Why would UV be excluded from the DLI?

[@DeBaccoUniversity]

Good question.... as it does have an impact on photosynthesis... www.researchgate.net/publication/261607138_Impact_of_Increasing_Ultraviolet-B_UV-B_Radiation_on_Photosynthetic_Processes

[@ace2044]

So DLI should drop when flipping to flower? I thought DLI should be kept the same or even increased when flipping to 12/12? I'm so confused >< I read every comment and you answered one who asked but the time stamps you gave didn't explain it :( could you please clarify if DLI should be decreased/kept the same or increased when flipping to 12/12? Thank you!!!

[@DeBaccoUniversity]

Goal would be not to drop DLI, but it gets harder to achieve due to the reduced duration. this is why the highest PAR is used during flowers to help keep the DLI as high as possible.

[@ace2044]

@@DeBaccoUniversity Thanks so much for your reply! Glad you said that. Those charts that say to drop DLI at flip are really confusing. thanks again and love the videos!

[@elliotte1981]

very rare but very important information. I`m trying to automate dimming of my Quantum Boards + UV + Far Red. Far Red must rise in the morning from 0 to 50% and then the main light starts from 0%. Both they accelerates to 75% and here UV starts rising. All lights get up to max. At the evening all the lights are dimming in reverse order. How do you think, is this plan correct? Have you ever wondered how the spectrum of sunlight changes during the day? Its veri interesting. Thank you. Upd. Just found your video about Spectrum Comparisons)))

[@DeBaccoUniversity]

The sunrise/sunset dimming has not been shown to offer much of a benefit so on and off is fine for the plants. While the actual spectrum may shift, there is an ideal for the plant so the goal is to provide this ideal in the greatest duration to help maximize yield. You do not need to get into small details.

[@ph1ogic]

depends on cultivar imo

[@DeBaccoUniversity]

This can result in some variability, but overall the plant still has essential requirements.

[@jccuchvjvj]

For 10 hours of a day can I increase the ppfd? - cheaper electricity. How much should I increase it, for what DLI? I'm thinking to give it 1200 ppfd in the center for 10/14 without CO2.

[@DeBaccoUniversity]

DLI of 65 moles per day is considered to be the threshold for optimum growth and photosynthesis. You may have to perform two separate calculations an intense light cycle and a normal light intensity duration to best match your growing situation.

[@jccuchvjvj]

@@DeBaccoUniversity as I understand 65 is possible in a 24/0, but for a 10 hours a day I should aim at max at 40 what is equal of 1200 ppfd per 10 h +-.

[@glennbonnici8883]

So i can give my plants up to 65 moles per day during veg ? Isn't 600 par enough for veg with 18hrs on ? Regars

[@DeBaccoUniversity]

Ideally that should be enough, but the plants could take more as is the case with outdoor locations.

[@andrerobichaud1333]

PPFD in µmol/(m2sec) ; so if you multiply m2sec you should display the formula as: µmol/(m2*sec) and not µmol/(m2/sec). You don't divide by sec you multiply. Also it should be said as µmol/m2sec and not per sec. Or even better µmol/(m^2·sec) in Excel.

[@DeBaccoUniversity]

The PPFD unit is measured in micromoles (one micromole equals 62 quadrillion photons) per square meter per second (µmol/m2/s). This means PPFD is the amount of PPF that arrives on each square meter of your crop at any given second. www.monnit.com/support/knowledgebase/sensors/what-are-ppfd-and-ppf-measurements/

[@alistaireandrewautida2915]

How to calculate DLI outdoors where there is a varying intensity of light? please answer

[@DeBaccoUniversity]

Take a reading every 10min (see 2:18 in the video for an outdoor graph) and develop an average.

[@joewuttiwat3254]

Without co2 max intersity that plants can use is no higher than 900

[@DeBaccoUniversity]

Goal is to reduce all limiting factors in the growing environment.

[@dano9411]

Algorithm

[@DeBaccoUniversity]

Thanks for your help with this.

[@Easy-my9gk]

MIGRO, not micro ;)

[@DeBaccoUniversity]

Correction was made the Mr. MIGRO himself and we even did a collaboration so check out the playlist.

[@Brian-bw3uu]

There's a strain called Trump?

[@DeBaccoUniversity]

I am sure it exists somewhere....

[@Monkey-vc3wh]

Not a very useful video. Very dry and technical unless you just love hearing random numbers spoken. You could leave out the math examples. I had math in grade school and understand simple multiplication and division just fine thanks. All this info is available in easier to follow packages

[@DeBaccoUniversity]

Not everyone is as fortunate as you so this helps provide the steps so growers can calculate their own DLI.

[@therickdarts180]

way to oversimplify math...lets talk about diefferent strains length of life... man your bad at this as a professor.

[@DeBaccoUniversity]

The plant does not factor into the DLI as this is looking at accumulated light to a surface and is not plant specific.

[@kingcola3849]

So how do you get that 60+DLI without waisting energy or using co2 my plants are in flower on a 12/12 schedule at 900 par and my DLI is 38.88 will I be ok

[@DeBaccoUniversity]

You need more PAR, but need to adjust other conditions. Based on your description your plants should do well, but may not reach their maximum potential.

[@kingcola3849]

@@DeBaccoUniversity so I'll have to use CO2 in order to achieve maximum yield?