Can Your Lights Be Too Bright?

Delps8

Well-Known Member
Girl Scout Cookies photo, three and half self watering pot, Updayday LED 700W. Oh two and half months old getting ready to flip.

One plant acts like it was getting too bright a light. Leaves curling.

I turned the light down and my Son moved the plants around
When the leaves curl, you're at the light saturation point for the plant so turn the dimmer down a few % and your plant will be "well fed".

How quickly did they uncurl?
 

amneziaHaze

Well-Known Member
Get a ppfd phone app turn to lux
Quick Guide – Lux Levels for Optimal Cannabis Growth

Life StageMaximumGoodMinimumVegetative
70,000 lux40,000 lux15,000 luxFlowering85,000 lux60,000 lux35,000 lux

< 15,000 lux – sparse or “stretchy” growth – plant isn’t getting enough light
15,000 – 50,000 lux – a good amount of light for healthy vegetative growth
45,000 – 70,000 lux – the optimal amount of light for cannabis plants in the flowering (budding) stage. If grow lights produce a lot of UV light (such as LEC), stay on the lower side of this range
70,000 – 85,000 lux – a lot of light, some strains thrive at this light level, but some plants (especially auto-flowering and Indica strains) lose their top leaves early under this light intensity. At these levels, lights need to be kept further away for healthy growth
> 85,000 lux – at this light intensity, you’ve hit the plant’s “saturation point” which means your plant can’t use all the light (most strains will experience light bleaching or other major signs of stress at this level!)
 
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