Is this light burn or nutrient burn?!

The brown spots seem to be more on the fan leaves So I ended up cutting off the fan leaves and gave some Cal Mag. I hope I did right.

Anything on the bottom of the leaves? Picture of whole plant?

I’m battling spider mites right now but caught them early…not sure on yours…I would probably just add the calmag and monitor to see if it gets worse.

I get it, we all want things to go perfectly, rarely do they.

Happy gardening


Hard to tell off the plant. Looks like heat stress but usually both nutrient and light burn get the tips. Fill out a ticket.

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As @Derf02368 mentioned above regarding spider mites, be sure to have a close look through a microscope asap to rule pests out!! I lost 25 plants that were ready to go into flowering due to Russet Mites. I also thought it was some sort of deficiency but by then it was too late.


This is the bottom. @Derf02368 Also do you know why the stem has that split down it. It’s also like that on majority of her. I will post pics of whole plant in a few. Waiting for lights to go on. (6:00pm)

Ok, so in my opinion it looks like a couple of things might be going on.

  1. Possible spider mites, treat with your choice of product.

  2. Your soil could be too “hot”… causing a little nutrients burn…maybe…

I’m no expert, just my experience.

Looks like heat stress and a foliar spray used with the lights on. Possible calcium deficiency. But the rings look like water drops where left to sit under a grow light. What is your input pH?

What’s the temperature swing? Highest with light on and lowest when off?

I’m basically ruling out mites, if they caused that much dmg there would be webbing.

Leaning twords a foliar spray or pH fluctuations