Trying to remember what PPFD is the most plants can handle in veg and flower

I haven't ever grown but I'm finally getting to the point where I an afford to in 6 months or so. Used to read a lot about LEDs on here. It seems like 800 to 1000 PPFD was about all plants could handle. When I build my cxb3590 setup I want it to be blasting like the sun lol. Any advice would be appreciated.

400-600 & 800-1000

Need CO2 to take advantage of higher PAR. Under those cobs, you should get great growth and bud development with 400-600 flower and 250-400 in veg.

I use Luminus, and i can tell you, the less light, the more tric development, aka frost. and when i got PAR over 700, i seen little value of blasting them with photons. although strain dependent also i guess, but I like OGs and they hate bright lights it seems. and run 3500K for all if you can.

800 at least, 1200 at the most is what you want. I would aim for 850-1100 optimally. Anything above 1200 can slow down plant metabolism, cause photoinhibition, or even cellular breakdown at around 1500+. Especially without supplementing CO2. It’s not a guarantee, just a rule of thumb.

InTheValley said:

Need CO2 to take advantage of higher PAR. Under those cobs, you should get great growth and bud development with 400-600 flower and 250-400 in veg.

I use Luminus, and i can tell you, the less light, the more tric development, aka frost. and when i got PAR over 700, i seen little value of blasting them with photons. although strain dependent also i guess, but I like OGs and they hate bright lights it seems. and run 3500K for all if you can.

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With respect to you, I don’t think I’d bud with less than 700-800. I think I’d veg with more than 250, though. 400-600. Not that those numbers won’t work, I just feel like they’d get stretchy to an unhealthy degree with light that low.

You should check out growmau5 on YouTube. Or the tech talk with grow maui and green genes garden. Both of those guys are on YouTube. Gene owns Pacific Light Concepts and Mau5 (mouse) works with Chilled LED. The tech talks they do are really deep dives into led lighting. I recommend downloading it to listen to or watch it a few times. There is ALOT of good info. It took me a few times before I even knew what they were talking about.
Another good one is the dude grows show that had Mau5 sit in and explain led to Scott real

Thank you guys for all of your responses. Everyone on RIU is just as helpful as I remember a couple of years ago.

So if I put 1 cxb 3590 for every square foot I will have plenty of PPFD to veg in...and more than enough to flower at some point if I decide to use it for that...

Why do you want to use CXB 3590? There are better chips out there, Bridgelux Vero29C, Luminous CXM-22, Citizen CLU048-1212, Citizen CLU058-1825, etc. If you want 1 cob per square foot for veg I would consider smaller/cheaper cobs like the 1212 or CXM-22 since you're not going to be running them over 30 watts each.

Rahz said:

Why do you want to use CXB 3590? There are better chips out there, Bridgelux Vero29C, Luminous CXM-22, Citizen CLU048-1212, Citizen CLU058-1825, etc. If you want 1 cob per square foot for veg I would consider smaller/cheaper cobs like the 1212 or CXM-22 since you're not going to be running them over 30 watts each.

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I guess when I was reading about this a couple years ago they were the most efficient COB on the market. If I'm going to spend the time and money to invest in something I definitely want to go with the best of the best right away even if it means I don't get as many. I can always buy more but I don't want to throw money into crap I'll just want to upgrade the next season. Probably go with 3500K and I want something that can hit 800-1000PPFD should I eventually decide to flower under them. I remember the cxb 3590 ran at 56% efficiency running at 50 watts. I definitely want something that efficient or more. What is the most efficient cob on the market now?

I remember CXB3590 begin about 50% efficient at 75w, back in the day for the 3000K 80CRI spectrum. Now for instance, the 3590 3000K 90CRI BD bin if we assume LER of 280 is 46% efficient at nominal current. Vero 29C 3000K 90CRI at same wattage is 51.5% efficient. Vero 29C is 56-58% efficient at 45w depending on variant. CLU058-1825 should 60-62% efficient at 50w depending on variant.

You could hit 1000 PPFD running Vero29C at 32.5 watts if you're wanting to be extreme about it, but the smaller cobs can save some money on the front end. I'm not up on those performance curves, but you would probably be looking at 36-38 watts per foot.

Rahz said:

I remember CXB3590 begin about 50% efficient at 75w, back in the day for the 3000K 80CRI spectrum. Now for instance, the 3590 3000K 90CRI BD bin if we assume LER of 280 is 46% efficient at nominal current. Vero 29C 3000K 90CRI at same wattage is 51.5% efficient. Vero 29C is 56-58% efficient at 45w depending on variant. CLU058-1825 should 60-62% efficient at 50w depending on variant.

You could hit 1000 PPFD running Vero29C at 32.5 watts if you're wanting to be extreme about it, but the smaller cobs can save some money on the front end. I'm not up on those performance curves, but you would probably be looking at 36-38 watts per foot.

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Thank you. Can you explain the color rendering index to me? I just read about it again last night, but after 2 years of not paying attention to much of this my brain is still having a hard time processing all the numbers lol

owsleygarcia95 said:

I guess when I was reading about this a couple years ago they were the most efficient COB on the market. If I'm going to spend the time and money to invest in something I definitely want to go with the best of the best right away even if it means I don't get as many. I can always buy more but I don't want to throw money into crap I'll just want to upgrade the next season. Probably go with 3500K and I want something that can hit 800-1000PPFD should I eventually decide to flower under them. I remember the cxb 3590 ran at 56% efficiency running at 50 watts. I definitely want something that efficient or more. What is the most efficient cob on the market now?

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56% comes from calculations from the datasheet, which didnt prove quite acurate in real life testing by Cobkits here on riu and by ChilLed in a sphere test. Vero/citizens/luminous comparable chips are more efficient at same power.

@owsleygarcia95 Hey I'm still trying to understand all this. But As far as I know the CRI % is how close it matches the sun. So 100% is just like the sun. I could be totally wrong. So if someone out there can tell me if I have understood that properly. I don't think it counts the spectrum we don't see like infrared or ultraviolet . Like Lumens are the measure of what the human eye can see, and par is the whole light spectrum beyond what our eyes can see.
please someone verify if I was paying attention the last two years. haha

bearded.beaver said:

@owsleygarcia95 Hey I'm still trying to understand all this. But As far as I know the CRI % is how close it matches the sun. So 100% is just like the sun. I could be totally wrong. So if someone out there can tell me if I have understood that properly. I don't think it counts the spectrum we don't see like infrared or ultraviolet . Like Lumens are the measure of what the human eye can see, and par is the whole light spectrum beyond what our eyes can see.
please someone verify if I was paying attention the last two years. haha

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Cri is how well a light source renders colors, 100 being it does it as good as sunlight. Doesnt quite mean its the same as sunlight as the sun has infrareds and UV and color rendering is a bit more complicated. As far as LEDs: high cri means more red in the spectrum but at a cost in efficacy.

@Rocket Soul
So I almost knew what I was talking about. I remember @grow mau5 talking about on the Grow tube round table

owsleygarcia95 said:

Thank you. Can you explain the color rendering index to me? I just read about it again last night, but after 2 years of not paying attention to much of this my brain is still having a hard time processing all the numbers lol

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For LED higher CRI has more red/deep red. Better spectrum, slightly worse electrical efficiency.

Rahz said:

For LED higher CRI has more red/deep red. Better spectrum, slightly worse electrical efficiency.

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So what CRI would you recommend?

When I was in Colorado a couple years ago, I saw some guys vegging plants to 6 foot tall 2-3 foot wide bushes in 3 months. They were essentially doing it by putting it them in a room with 25 or 30 1000 watt lights they had bought used and they hadn't even changed there bulbs in like 2 years. They put them in green houses with ridiculous results. I'm trying to do the same thing on a small scale off grid. I will have to veg under LED with a generator because I'm poor and I'm going to buy some dirt cheap land more than likely in ME because flower is still worth something in Maine. Probably going to veg in one end of a shipping container and use the rest for storage...I'm only going to veg 6 or 12 plants each with there own massive green house...and then I'm getting the hell out of ME for the winter lol. But if I'm investing the money in the COBs I want to build some that are capable of putting out 800 - 1000 PPFD because I'm sure I'll want to do indoor runs eventually too.

flower 6-12 plants*...coffee hasn't kicked in yet lol