What is the best PPFD for veg and flower?

Currently been using a meter to check the PPFD at the canopy, and I am getting between 420 - 620 PPFD at the current lights height in a 3 x 2 area. I have not been measuring height, instead the PPFD at my plants and then making adjustments on that.

I have two autos in flower right now, and a couple more a couple weeks behind in veg. My flowering plants are getting 490 - 620 PPFD, but what I am worried about is my vegging plants. They are getting 380 - 550 PPFD, and the new growth tips of a couple of the vegging plants are turning light green. I am assuming they are being exposed to too much light.

What PPFD levels do you shoot for in veg and then flower? I could scoot my vegging plants to the far-side of my 4 x 2 tent and they would be getting around 240 - 320 PPFD beyond the outside edge of the light.

You should be fine.
I typically see lighter color new growth.
The plants see over 2000ppfd when they grow outdoors, so they are capable of tolerating much higher intensities.
I find that unless you're supplementing co2, going over 800ppfd was counterproductive.
300-500 ppfd will veg.

Depends on the strain, in flower for example some will get bleached tips at a light level that others will handle with glee. Also depends on the phase of flowering. You just have to learn to read your plants and tell what they want.

roots_indoors said:

What PPFD levels do you shoot for in veg and then flower?

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In veg usually around 700 umols for bigger plants, 500 for babies. In flower anywhere from 700 - 1200 depending on strain and what part of flower. Hit em hard as they will take during the first half to 2/3rds of stretch/flower and then dim to prevent fluffy foxtailed buds.

Renfro said:

Depends on the strain, in flower for example some will get bleached tips at a light level that others will handle with glee. Also depends on the phase of flowering. You just have to learn to read your plants and tell what they want.

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My GSC’s all are slowly getting lighter tips from more light, but a couple other strains don’t mind. Very interesting.

Renfro said:

In veg usually around 700 umols for bigger plants, 500 for babies. In flower anywhere from 700 - 1200 depending on strain and what part of flower. Hit em hard as they will take during the first half to 2/3rds of stretch/flower and then dim to prevent fluffy foxtailed buds.

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Awesome info. My light is capable of hitting these numbers, I’ve just been hesitant on bumping any of them over ~630. I started them for 3 weeks under a COB, and when I switched to the QB, the tips started bleaching out on a few of the plants. They were only getting around 500 at that time. I’m thinking that it’s possible they could be more receptive of the higher levels if they started under this light to begin with.

I should mention that I run CO2 enrichment allowing the plants to make use of more light, nutrients, water and warmer temperatures. All go hand in hand in the right proportion for your strain.

Renfro said:

I should mention that I run CO2 enrichment allowing the plants to make use of more light, nutrients, water and warmer temperatures. All go hand in hand in the right proportion for your strain.

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I have a 5 gallon yeast CO2 bucket that is on a shelf above my tent. An air line runs from the sealed bucket to a floor fan. I have about 3 gallons of sugar water and yeast mixture in the bucket. It gets changed 2 weeks. I don’t have a CO2 meter so I can’t test the tent levels, but I do know that bucket is putting out CO2 at least. Might only haves bumped levels slightly higher but it was DIY and I had the stuff laying around. Figured it wasn’t gonna hurt.

GBAUTO said:

You should be fine.
I typically see lighter color new growth.
The plants see over 2000ppfd when they grow outdoors, so they are capable of tolerating much higher intensities.
I find that unless you're supplementing co2, going over 800ppfd was counterproductive.
300-500 ppfd will veg.

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Solid info. Thank you.