Odd leaf damage with dark spots underneath

I really have no idea what this is, but my otherwise seemingly healthy plants have started to display some very odd damage that looks dark brown / orange on the top side with a dark gray / blackish color on the bottom of the leaves where the damage is...They have not slowed down their growth at all, and actually appear to be growing even quicker than before I discovered the issue which is even more confusing, but also makes me think that it's not nute burn like I had previously assumed...

Medium: Organic soil mix with most of the usual suspects (guano, castings, kelp meal, aloe, etc)...
Lighting: 600w MH
Temps: High 70s to Low 80s
Watering with 6.5 pH water - haven't been feeding besides a couple light foliar feeds of neem and Dr. Earth 3-3-3 all purpose liquid gold.

Besides those odd spots I thought the plants were looking pretty damn good and then the spots started spreading out a bit making me slightly concerned. I have not spotted any insects yet, but I'm sure that is one possibility. I'm all ears if you have a suggestion, idea or diagnosis...thanks in advance
-ayr0n

PS: Here's the journal of this grow - https://www.rollitup.org/t/gg-bastard-series-colombian-gold.848443/ - might offer some insight to what's going on if anyone is feeling inclined to playing plant doctor

I've had those distorted leaves from drowning during veg, grew out of it, but spider mites can have that effect too.

That black stuff is odd, are you sure that's not from the foliar spray? Does look a bit like some black mold or something.

Nepenthes said:

I've had those distorted leaves from drowning during veg, grew out of it, but spider mites can have that effect too.

That black stuff is odd, are you sure that's not from the foliar spray? Does look a bit like some black mold or something.

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idk man, i don't see a neem oil based foliar spray causing black mold but I guess it's possible...they are dry within 25-30 minutes max because the fans and the strong airflow of the outtake...

I don't know how I could have been so blind but now that I saw what's there I'm seeing them all over - it's fucking mites -.- Wasn't spraying the bottom side of the leaves thoroughly enough I guess.

The good news is they died on contact from the neem oil spray - bad news is there's probably other stages of life hanging out that I'll have to deal with. The ladies appear to be resisting the damage fairly well so far, but I did create the perfect conditions of a spider mite infestation. The tent's humidity is around the low 20s and temps in the low 80s which is exactly what some species of mites thrive in :X Gonna keep the ladies well hydrated because water deprived plants are more susceptible to mites. Planning to work out a more thorough offensive and put together a better Defense for the future. Fucking mites

Nepenthes said:

but spider mites can have that effect too.

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Good call @Nepenthes - you were right The 'black stuff' I described was actually dark green - the top side of the leaf showing through from the bottom. They're like eaten away from the bottom up :X Pretty nasty lil creatures but they won't be around for long.


From what I've seen they don't appear to be a 'webbing' type of spider mite...more of a I'm gonna suck holes right thru your fucking leaves and crawl around without making webs kind of mites. They kinda freak me out...little creatures that suck up living cells 1 at a time while laying nasty little eggs that can produce new creatures whether the eggs were fertilized or not? Nightmarish fucks.

Glad to hear you found the real cause man. Your plants look very healthy and strong otherwise.

Declare war on those fuckers. Good Luck Dude.

Think I killed em lol...Not gonna underestimate the problem but if they're still around I'll be surprised.



GG #1 (back left) got hit the hardest but the others look like nothing ever happened unless you look real close to some of the lower fans

I about had a heart attack thinking you had something wrong with your grow. Its funny how sometimes we just need an extra pair of eyes to see what we cant see Id hit em everyday with your miticide till you see flowers I hate those fuckers. I may have finally beat these bastards but they always surprise me how resiliant they are. They will lay dormant, they can even lay somewhere in a cool spot and just chill for awhile till they get a breath of warm air then they are up and about again. Try putting vasoline around the top lip of your pots, they get stuck in that trying to go from plant to plant (provided they arnt touching other plant infected leaves))

Be careful with your watering..you may be creating conditions for powder mildew. If so, it's easily fixed with neem or the old baking soda, dish soap, vegtable oil dissolved in water method.

Just giving you something else to worry about.