PAR sweet spot for plants?

I have a 132w qb288v2 arriving tomorrow. Current light is a viparspectra 300w (136w). PPFD tests are showing that both lights are near the same dead center (a little over 500 at 18”). Once you get to the 12” and 24” mark is where the QB surpasses the blurple. I’ve read that you reach saturation at 1000 PAR. What is cannibis’ sweet spot when it comes to PAR? Is it plant dependent or is it like PH where where there’s a range you want to stay near?


At you one more time lol @dbrn32


Thanks bud! Forgot the tag

No worrys mate :kangaroo:

That’s really what the intensity is over the entire canopy, not just the measured reading at center directly under the light. A ppfd average of between 600 and 800 umols per second is a really good spot to be.


Awesome, thanks!

look at Migro videos on you tube,
Shane does testing on many different kinds of lights and maps out their coverage.!!

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I think I’ve watched them all, lol. I just never saw what the sweet spot range was across a plant canopy. I have a PAR meter coming in so I can adjust my light so the canopy is in that perfect range.

he uses a color coded mapping, red ares r over-saturated, and i can not remember the other colors… LOL

deep red = toxic levels
red = over-saturation 1000 - 1500 umols/m2/sec
gold = flower power 750 - 1000
yellow = low flower growth and high veg growth 500 - 750
light blue = okay veg growth 250 - 500
dark blue = unusable amount of light


Gonna need to rewatch. I am colorblind so I may have missed that part

he posts the actual reading’s numbers too, i think…???
they say cannabis effects something, but i can’t remember what it is…

Yeah, I saw all the ones with numbers. He’d test the lights at different heights and show the ppfd value. But I never saw one that showed what the optimal value was for plants. I knew 1000 was the saturation point but I never saw this one you posted:

over-saturation 1000 - 1500 umols/m2/sec
flower power 750 - 1000
low flower growth and high veg growth 500 - 750
okay veg growth 250 - 500

:point_up_2: that’s what I was looking for. Thank you!

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300–350umol/s will be needed for growth, 700–800umol/s will be needed for flowering, click here to read this essay , it will help you