How Much PAR Do Cannabis Plants Need? - Understanding PPFD & PAR

[@LexBlazer]

thanks for watching everybody! I published this on YT just cause it's such an important episode. See all the content you've missed the last few weeks on my Off-YT platforms! Linked to in the video description!

[@EthanMcKee.]

Oh boy! Another video about lights. It's almost like this channel has turned into the Light Bulb Show. Give this shit a break man we are getting absolutely sick of it.

[@LexBlazer]

There's actually been a bunch of content in the past 3 weeks that isn't light-related...it just isn't being uploaded on to YT anymore. You gotta follow me off-platform. Plus, light content is important - your light fixture and light is your #1 most important piece of equipment. Nothing else impacts yield more. There's also nothing except light your plants can't make it more than 72 hours without.

[@EthanMcKee.]

@@truthfulreviews488 some people just like to act like they are above it all when it reality they are the most weak kneed cowards on this earth

[@EthanMcKee.]

@@truthfulreviews488 I believe I will unsub from this half ass channel. This fool doesnt even show us what the bud looks like after he is done with the grow what kind of shit is that. For the past 10 weeks it's been nothing but lights and scientific bullshit.

[@m.w.2098]

@@EthanMcKee. Hi! While sifting through your shit postings I see you're upset about his content. Thank you for sharing. I have a solution! Stop watching, unsubscribe, and quit posting here! See! Wasn't that easy? Have a nice day, God bless your heart!

[@dtwistrewind7361]

Heat stress is easy to spot but light stress is a completely different beast and much trickier to resolve, brighter isn't always better, took me a while to realize the difference.

[@joaoalbertofn]

Amount of PPFD per stage of growth: - seedlings: 150-400 - vegetative:. 400-600 - flowering:. 600-900

[@lunareclipse1482]

These values are for Indica strains. Sativa loves the heat, omg; even guzzling down 1400 PPFD.

[@Rizik1986]

Are these #s for autos or photos?

[@paulmildner6357]

I literally thought about this a few hours ago and now here's this video explaining everything

[@sonicrising6614]

No hat or sunglasses?. I barely recognized you lol. Great video.

[@supersixone9848]

Lol foreal

[@glinda9243]

Same! 😆

[@vwvwso4176]

I like him better without the shades 😎. Great video

[@trippsmclovin]

He's not in the grow room, gotta have protection :)

[@bradgardner6952]

Thank you for making it simple to understand. Peace ✌️ ☮️

[@williebssnap3689]

I just simply love all your videos and you are the main person I listen to. I want to support you one day

[@AverageJoe8686]

PPFD = [ (uMol/m^2) / sec ] is a better way to write it, which gives the physical intuition of the concept. uMol is the number of things (Photons)... and m^2 is the square area. uMol/m^2 is the things in an area. [Things in area]/second is how many things are in an area if you count for one second. This idea lets you average it all out so you can get one number instead of hundreds which is confusing.

[@luxx1346]

You always seem to release your videos right went I need them. I happen to be buying a new light and this is exactly what I needed, thanks man great video.

[@unknownip6741]

Great... I really needed this.. know what it means... but don't know how much I need

[@michael2305]

depends on what you're growing some plants lettuce for example I think doesn't need much at all if you wanna grow some sticky tho these plants need a ton of light (they can use up to 1000 umol/s and with CO/2 and perfect conditions even close to 2000)

[@tenthplanet3342]

I loved the statement about the university 👍

[@michaelteran3844]

You are a great Teacher. I wish I could contribute. I am on a fixed budget from a disability. I am a recovering alcoholic with stage 3 cirrhosis. Cannabis has helped me in recovery for I was at a stage 4 just 2 years ago with a bleak outlook. I quit alcohol but realized I was self medicating for anxiety. Well I didn't want to use anti-anxiety medication for they are much more addicting and harmful in my opinion. Plus I am on a plethora of medications to treat the symptoms of Liver Disease and not to mention the most important one costs over $2500 monthly for 2 pills daily for life. It's called Xifaxan 550mg. Ridiculous. Anyways I wanted to thank you for your lessons. I tell and talk about your life lessons in cannabis cultivation. I was using Sunleaves Luma 2.0 ballast and hood but I cannot afford to grow using that. Hopefully I will afford a decent small LED GROW light so I can try my luck indoor once more. Just harvested way small grow for how much power I had to use🤬 very discouraging it was. It was the lights being too much in a small area.

[@jamiezeederberg8832]

Nicely explained. Greetings from South Africa

[@nickking6371]

Thank you for eloquently consolidating lux/ppfd to 20 seconds. That but for all information. Get to it humanity! Haha well done bro.

[@comfortablynumb9342]

The university of Mississippi is the only place that grew with federal permits and they supply the few people who got cannabis from a federal program. They have research because they're the only ones who are allowed by the feds. Their info would be great to access.

[@littlenugs9942]

Just got my first par meeter. And flipped to flower. I had to get the par meeter due to my lights being so nice I burnt the last crop a little

[@arkinner]

Nice lex. I liked it. You gave me a better understanding on this subject. Thanks man.

[@TRDPRO312]

using this to teach a friend who only thinks in terms of lumens! Thanks for the great videos, really big help.

[@a12vguru]

Lumens is to measure light for the human eye wavelength, not for plants you need PAR to get a true reading for the plants not his eyeball.

[@bigbigjoel9710]

Welcome back!

[@LexBlazer]

Not really back; like, today's actual new episode won't air on YT at all...this episode is from a week ago. just didn't want to keep this particular episode off YT - PAR is fairly important stuff.

[@TeW33zy]

Pt.2.....if you want fast growth instead of those stunted plants yajl grow. Seedlings 140-175 ppfd first 7 days, 200-250 next 5 days and finish seedlings off at 275-300 ppfd (never ever 400). Vegetation 350-400 ppfd first 5 days and so on and so on.

[@bastianm5478]

Hey TeW33zy, your comment regarding ppfd is exactly what I've been looking for. Can you provide a plan? So far this is what I've got, please correct any mistakes and help me complete it. Day 1-7: 140-170 ppfd Day 8-12: 200-250 Day 13-21: 275-300 Day 22-30: 350-400 Day 31-60: 400-600 ppfd Day 61-90: 700-900 ppfd I'm using the Photone to get an approximate measurement. I've just written some suggestions without knowing anything.

[@TeW33zy]

@@bastianm5478 I am a Sr. Biosystems Engineer, Agricultural. I got you covered. Ok so ppfd, C02 and Nutrient ppm are a function. See Below The Nutrient feedings are based on using Fox Farm Soil from the beginning. You shouldn't have to feed Nutrients until mid Flower. Feeding in veg only should occur if your plant eats up all the food in Fox Farm soil. Your plants leaves will tell you if so. This generally happens only if you stayed in a particular pot size to long or past 3 weeks. Generally, Fox Farm Soil has enough reserves until your next Transplant. If u plan to stay in the pot size longer than 2-3 weeks then feed accordingly. Usually 1 Feeding will give you another 2 weeks. Seedlings: Day 1-30 = 165ppfd (party cup) Day 31= Transplant to 1 Gallon Day 31-45 = 200 ppfd Day 45 = Transplant to 3 Gallon Day 45-65= 250-300 ppfd Day 65 = Transplant to 5 Gallon Day 65- until Flower 300 ppfd (Transplant how you best see fit, u do not have to follow my scientific regimen) Transition to Flower Day 1-30 = 500 ppfd CO2 700ppm Day 35 -75 = 700 ppfd CO2 900ppm ⚠️ Warning ⚠️ Do not go over 750 ppfd without CO2 supplementation of 1000ppm or greater or your plants can/will turn to a hermaphrodite. C02 must always be 200ppm above your ppfd. C02 supplement table below: 500 ppfd = C02 700 ppm 700 ppfd = C02 900 ppm 900 ppfd = C02 1100 ppm 1000 ppfd = C02 1200ppm (83°F leaf temp is required for adequate photosynthesis for ppfd above 700) Tip: Never exceed 1,000 ppfd otherwise you burn the capitate-sessile, capitate- stalked, and capitate-bulbous trichromes and volatize your flavornoids, cannabinoids, thc and terpenes. You deplete the aroma by 85% as terpenes are extremely volatile. They evaporate at temperatures above 71°F after harvest and at 87°F or greater during flower from heat occurring from ppfd above 1000-1200. Nutrient ppm should match your ppfd. Feed Nutrients every 4th watering. Ppfd, C02 ppm and Nutrient ppm should match. Except C02 ppm should always be +200 to allow the plant to keep up with carbon dioxide.

[@KayFiedler]

Your the boss, I wish I could help, but I’m on disability, from car accident.....thank you..🙏

[@shaolindreams]

So many funky lights out.. all slightly different.. gets a bit confusing how good is one over the other. Thanks for the video.. I really need to get a par meter now so i can adjust my lights accordingly.

[@Des420]

That is money better spent on environmental control or more lighting. Unless you have money you don't care about, a home grower doesn't need a PAR meter.

[@shaolindreams]

Why not

[@Des420]

@@shaolindreams Because it's expensive and you don't need it the same way you need to control temperature or humidity.

[@caminochef1132]

600 PAR @ 18 hours is the exact same amount of light as 900 PAR @ 12 hours. When you say "400- 600" for Veg and 600 - 900 for flower, it's bad info, misleading. If someone is switching to flower and running at 600 PAR, if they switch to flower and keep it 600 they're cutting the light by about 30% over all. If you're switching to flower and running at 500 PAR. Just multiply 500 x 18(hours). Take the total and divide by 12 (hours), that's the same PAR as 500.

[@Retrakk]

University of Mississippi got a federal grant for the study of cannabis, which is why you see so many published articles from the institution.

[@rationalbushcraft]

I assume that Mississippi is doing that research because they have something to do with the government marijuana farm in Mississippi. That farm is the only supplier for research in the US.

[@LexBlazer]

lol yes, i looked into this after; it's exactly correct. They're involved in the last remnants of the Federal medical program.

[@soulseeker42388]

Other then what is seized throughout the country from the major illegal grow ops

[@ellisjk1409]

This helped me, thanks. Of course I subbed.

[@danielcardenas9924]

Best cannabis channel 👍🔥💨

[@mykal2803]

Technically you go over 1000ppfd also if you introduce more co2 to the grow, itll increase yield and speed of growth.

[@lunareclipse1482]

We read the same book and watched the same movie. Ambient CO2 is 300-400 ppm. CO2 for extreme lighting - 1200-1500 ppm. You also need more nutrients, water, heat, and air current management. Amen, My Brothers in Ribosomoes.

[@soulseeker42388]

University of Mississippi is the only college to have a permit the study by the government

[@LarsLarsen77]

They also grow the only legal research cannabis.

[@soulseeker42388]

@@LarsLarsen77 that is actually false there us a government funded research facility here in Missouri in Eureka that grows its mainly for the research into cbd but still the fact remains there is another government funded research facility and probably more that we just dont know about through out the country that are ramping up for full legalization like Canada but its big tobacco and pharmaceutical companies that are greasing the plams of politicians

[@JesseJames83]

Not why, but WHY!?

[@paulfun8720]

Research my ass this university is part of the problem. They have suppressed research thanks to big pharma but they still needed a token "research" location and this is it.

[@m.w.2098]

Sadly true, their quality has been reported to be barely above Cannabis Ruderalis by the one federally legal patient that was interviewed. As far as claims to other universities having permissions from the govt, I know that there is current litigation over this because of the blockage, so I find the post about the Missouri university suspect. I do my best to keep abreast of these issues, but welcome new input always.

[@winnpierrepoint2939]

Ere lex, watched both your excellent videos on light, which do you think is better to use as a measure of good growing Lux or Ppf? Grand advice mate and like your style first indoor grow so still working things out, you been a wealth of quality info moosh, cheers

[@justinomar9210]

Right now I've got my seedlings at 800 to 1000 par outdoors showing no signs of stress

[@MinimalRastalien]

Nice video man, thanks.

[@TheCheapReefer]

PUR is most important which is Photo Useable Radiation . Which is based off the chlorphyll use . Atleast thats what we use for coral s

[@johnmiller2446]

Bestva is a hell of a light

[@davidbrandenburg8029]

high ppfd needs more carbon dioxide to get max growth

[@lunareclipse1482]

and everything else - nutrition, water, temp mgt, ect.

[@wolfeatsheep163]

Well spoken man thanks I'm a newb and have watched most of your vids and also dislike Google and fb and probably Amazon also and I use brave

[@hutchklutch2594]

The University of Mississippi has been the ONLY government controlled cannabis research and grow legally in the US since 1961. In 2016 they passed a bill allowing other institutes to study the plant but so far UM is the still the only one.

[@Jonekkk933]

Lex on point as always thanks bro interesting stuff

[@oliviermixtur5362]

Amazing video

[@brizalsgarden2646]

Great info. Thanks lex.

[@geokemical]

For me these numbers(everywhere shows same numbers) about ppfd for each stage dont work.I ve par meter and every time i try catch these numbers my plants stress.Do i do something else worng or its marketing?

[@davidsean1762]

Thanks for the useful info!

[@ansmerek]

Love the channel, love the content. One question. If sunlight is 2000+ umol/s in nature why do you recommend using levels so much lower? I run my grow tent above 1500 umol /s at all times, and in flower as high as 2500 umol /s with excellent results.

[@fakename7570]

+1 I finished my first grow...LSD-25 autoflower at about 1200 PPFD using Bloom Plus 3000 LED. Only plant I grew gave me just over 2 oz of dense, smelly, sticky flavorful, and very effective buds. Yeah for me!

[@Alchem1stt]

How are you altering umol? More lights or do you have a light where you can alter the PPFD

[@ansmerek]

@@Alchem1stt Current control drivers, or number of lights; or both. There is no realistic way to replicate sunlight though, not even close

[@ansmerek]

@@fakename7570 I expect at least 1g / W of electrical light power. With a 300W LED source I pull 10-12oz of top grade buds. That said, sunlight puts this to shame. I'm confident I'm not even at half, maybe even a quarter of the light I need to max out yields, but I really have no way to know

[@Alchem1stt]

@@ansmerek thanks for the quick reply. Doesn't a 300w light lose a lot of PPF even at 2ftx2ft? It falls down to 120 PAR at the edges, how can this be viable if 600-900 PPFD is desirable for flowering?

[@miclo-jb4ku]

I have a 600w viosun led in a 3x3 grow tent. And I just ordered hlg 260 rspec. I was thinking of keeping them both in the tent. Is that a good idea to try and get a better yield since they're both pretty small? Or should I take out the vivosun and just use the hlg

[@ch70]

Mississippi was part of a cannabis study by the US Govt. I think the remaining subjects of that study still receive cannabis from the govt??? The only people in the US the federal govt considers legal to possess.

[@maroonspirit7142]

Hey man i love your info

[@joshbeck289]

I have a plant in flower at 850 par no Co2 some spots are at 900 ppfd

[@Ackurafull]

Gracias!

[@Torontogtacleaners]

My issue is my led lights at 15% dim is already at 550 par am in veg I try putting it to 25% amd it goes to 1000 par it’s a 600 watts do I keep it at 15% meanwhile the manufacturer recommended 100% for veg ? Can u help me out

[@goldengod87]

Whats a lux meter do i need this and the par meter he talked about for my indoor tent in my basemnt??

[@ivorgreenplant]

when you say heat stress would that make the plants look a bit droopy after a lot of light .. leaves looking saggy cant hold there own weight ?

[@brainchildguru]

“Lex Blazer” was almost my porno name. Thanks for the great content!

[@jackofnone9439]

I don't know if it's just me or not, but I can't click on any of the links you put in the description. Just so you know...

[@LexBlazer]

holy cow! thank you for pointing this out....i have no clue what happened there. Fixing!

[@LexBlazer]

Yeah, that was super odd....never seen that before. it randomly deleted every beginning of every link, up to the www....i'll have to watch out for that in the future.

[@jackofnone9439]

@@LexBlazer No worries...hope you can get it fixed. Love your vids bro!!!

[@dienovandale4299]

DARE YA TO SMOKE A BONG FULL OF KILLER FLOWER !

[@kickinwinghotboi883]

Fun fact: The University of Mississippi (aka Ole Miss) has pot fields where they grow their own "test subjects"

[@michaelbogdovitz9479]

If you are running 1000 ppfd and up you should be running CO2 for your garden to be healthy and growing efficiently.

[@doomslayer9513]

Hey Lex, I got a question and really hope you can answer... I am growing 10 regular Afghani kush plants and they are 32 days old from seed, and I tried to rub my fingers around the main stem up and down to smell them, and 8 of those plants smells very soft and flowery (delicious), while the other two smells like sweat and piss, kinda like what you smell if you run on a treadmill at the gym... My question is, is that a good indicator to sexing my plants? like do I have 8 females and 2 males right now? Thanks in advance and hope you have a great day!

[@lunareclipse1482]

NO NO NO. A better indicator would be the pre-sexual traits at the nodes of young plants. Male plants have a penis or knob looking mini structure (stamina) at the node lol. What you are describing is genetics. All seeds contain different genetics - different phenotypes and genotypes. Go do some research. Also males plants grow taller and more distance between the nodes or branches (leggy).

[@robertschmidli2195]

Did the study from Mexico include soil nutrition and rainfall or manual watering?

[@juggernaut911]

Very useful Ty brotha

[@josuebueno6712]

i just need my paycheck im getting every thing ik for sure is gon make these lil seeds grow 🙃

[@LiteralHitter]

20'' canopy 250ppfd max on top no lens no reflector 8 weeks flowering 0.15$/W light fixtures -------------------------------------- 0.9g/W

[@matthewcooke1742]

Mid day sun is around 2000 ppfd

[@martinnunez4919]

Thanks bro

[@zackblack1824]

So how far would from your plants would you keep 2 Aglex 2000 watt lights with just the cobs on? Asking for a friend...

[@MrQteinteresa]

nice teacher glove

[@erotokritoswilliams3393]

Hello I would like to ask if a Mars Hydro TS 3000 LED Grow Light at 1095.6 umol/m2/s is adequate for a filled 4.5ft x 4.5ft tent! Would you instead go with something different? Thank you & Keep it Growin!

[@danielwatson4417]

how can you test this on the purple led full spectrum lights

[@Rasheedamcclintock77]

A lux meter is a Free App on your phone!

[@slackwatters9604]

I was at work for this one hurting really watch itdid you mention who got that light I did not catch it I got them at work how you doing today

[@LexBlazer]

for winners of any giveaways i do, just go to the corresponding video and check the video description. I always update with winner names - even on off-YT descriptions.

[@jonathankravitz4832]

Can you please recommend a decent par meter? Thank you in advance

[@Talonfrank1]

They got apps now on the iPhone 13. That’s what im using

[@javiergomez5129]

Good morning,i put my clones to flower and after a week went back to veg is that good? What will happen and how long till tbey go back to normal,thank u for your time and avise

[@lizdryburgh6243]

That's how old school growers determined the sex of the plant 🌱 before you could buy all female seeds, shouldn't do any harm

[@ashiha13]

How much PPFD does the sun give off on average cloudless days? I know it varies, but it helps to have something to compare against (a control).

[@FXPips11]

2100 par,

[@bquade70]

It's the only lab granted any access to study pot. Period. That's why it's not legal yet, and only one company has been able to market a CBD drug for epilepsy.....

[@pauldow1648]

Is there a good ppfd meter that does not cost $600 as shown on your Amazon store ?

[@bonsakoi7435]

Have you tried the app, Tent buddy or ppfd meter. For android? How accurate is it for par

[@23lnp]

Hi my friend, would it be possible to give me some advice please. Ive got the kingbo 2000w led ( 350w actual pull ) How far would you keep it above canopy in flower stage ?

[@dienovandale4299]

Graduate the distance weekly till you see bleaching Chow

[@brandysigmon9066]

I think University of Mississippi is the one of the very few places the government lets them study cannabis, I think it has or had a lot to do with a certain professor, I can't remember his name, this info would be easy to find

[@lunareclipse1482]

Ole Miss is the official and only supplier and researcher of marijuana for the USA govt. lol

[@pjerkraden6287]

Hey Lex what do you think of bestva LED one from the picture you showed on the start of the video?It is China made but good spectrum and ok PAR. Is it worth the money?

[@LexBlazer]

At any given time there are several brands of LEDs I reccomend (bestva is ok, but not one of my favs)...to see my up-to-date list of favs just go to my grow gear shop on amazon, linked to in any video description.

[@pjerkraden6287]

@@LexBlazer Ok thanks for the replay

[@charlesii5353]

Yeah I’m like 2grand

[@gaetanmottin1703]

how much PAR for seedling ?

[@davidbrandenburg8029]

over 1000ppfd and you need to add carbon dioxide for optimum growth

[@dienovandale4299]

If your buds are not rock hard , crystal coated to the stick ! YOU NEED M O R E PAR !

[@RoCkShaDoWWaLkEr]

CO2, nutrients and genetics are what determine density in my experience (growing cannabis for over 23 years on a massive commercial scale most the time, I currently only run 38x 1000 water license and have a 455 plant license). Also the right nutrients are a sure fire way to get "Massive" amounts of "Resin"/crystal.

[@dienovandale4299]

@@RoCkShaDoWWaLkEr no, just genetics , the rest ,is supplemental friend ! Chow .

[@johnbrown4442]

For PAR iPhone Korona has a free app.

[@Isejankhonojanem]

It’s because of the land it’s cheap there

[@kungfuhustle6363]

Oh shit 😎

[@goldengod87]

Do i need these meters, i have great equipment, orgganic soil, meters, etc. I did download a lux meter on my android phone but not sure if its reliable

[@creed981]

That depends on if you want to know how much light your plants are getting. I think every grower should have a lux meter. Spend no more than $60

[@marcjtdc]

wrong. 3:40 you can increase yields by using c02 and using the vapor pressure deficit method.

[@JohnConnor12]

True, but he was talking about how to increase PAR, not yield.

[@marcjtdc]

@@JohnConnor12 ok maybe I had a few too many plus weed lol sorry.

[@TheHst001]

nice melon

[@DRSATAN]

who is this man with no sunglasses that sounds just like lex blazer? is he like a double? oh is lex on vacation? well i hope he enjoys his vacation. and chicken salad is so good to eat as a sandwich. mmmmmm good

[@crowlsyong]

Thanks for fucking adding a paypal, bitcoin, and litecoin option. SO many fucking creators I want to support but I seriously hate amazon and I can't afford too many monthly subscriptions. THANK YOU. Sent some bitcoin. :)

[@crowlsyong]

Also your eyes look great. I'd love to see more of you without the glasses. peace n love

[@michael2305]

For rookies: PPFD = Photosynthetic Photon Flux Density, wich is measured in a lightsphere. As you can imagine - those are not realistic conditions for growing as the photons bounce around wildly in a sphere. Total PPF = Calculated PPF based on the efficiency of your LED chips (also not very accurate) Usable PPF = Amount of photons that actually hit your plants. (BINGO, that's the stuff we wanna measure!) How to do that? with a quantum par meter. I recommend shane's youtube channel since they are pretty expensive (300$+) He tests alot of LEDs in detail for their usable PPF and efficiency. He got his own company called "migro" wich is also the name of his youtube channel. They produce high quality LEDs too btw and are based in ireland. You're welcome.

[@esourteric412]

They only ppl that can grow federally

[@coreytripp9939]

bros got anime eyes wtf real life anime mentor

[@ShelRaiser]

Is his eyes AI?

[@ginpok6640]

i do hate amazon...

[@familyman1071]

I live in Mississippi we voted yes for medical canabis at 79% .The Law makers might be regressive but the fine folks here are progressive about canabis and guns.... two which you should never put the two together.

[@rhodes6840]

U of M

[@myoplex1]

You explained those values completely wrong. You stated the PAR value not the PPFD. 600-900 is what the PAR meter would read. The PPFD for 600-900 PAR would be 26-39 PAR/hr over course of 12 hour photo period (lights on time). You massively oversimplified that calculation. You multiply the PAR reading by the number of seconds in your photo period (ie PARx3600 seconds in a 12 hour light cycle) and then divide that by 1,000,000=DLI. Example (600 PARx3600 seconds)/1,000,000=2.16 PAR/m2 per second. That’s how many PAR (light) your canopy gets per square meter per second. Hence the fucking term “DAILY LIGHT INTEGRAL”... and by the way 600-900 PAR is WAY TOO much light even with CO2 supplementation!!!

[@FrostkingGenetics]

Stop the dribble and get to the point ffs

[@swissrims2575]

I have a 3000 watt full spectrum LED light and I have little baby plants that are about the length of a middle finger how high should this 3000 light be from those plants without burning them or hurting them I actually have the light about 4 ft from them right now is that too high