Spots in Late flower

Sick Plants & Problems
#1

Ive got a few girls in this tent all at 7 weeks and a couple branches with these spots on the leaves. Not all plants, only a couple branches and a couple fans here or there. I know im close and will probably ride ot out unless y’all notice something i totally miss.

Also know: late last week i had 2 nights that the power went out for 4-5 hours during lights on. No ventillation, nothing. Humidity kicked up to 80% for a good 6 hours, temps dropped to low 60s. Covid has been kickin my ass this last week on top of it. Got things rearranged with a everything back on track and additional 4" inline fan forcing dry air in after night 2. Better now Humidity 50/55, temps 68/83 lights off/on.

Could this be from water droplets when lights came on from condesation or something else? Doesnt look lile deficiency that i could discern with a pic. Inspect3d stems and buds with no obvious (at least to me) signs of rot, mold, mildew. Smells are good. Any help is appreciated.

Overall

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Most affected branches

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4 Likes
#2

hmm I would think calcium or potassium :thinking: if it was in bands I’d think ph swings. The little dots kinda throw me off a bit but overall, that’s my thought. I’d definitely double check the undersides of those leaves and ensure there’s nothing on there just in case :face_with_monocle:

10 Likes
#3

I agree. I’ve had that in the past when I used to grow in coco. I was adding extra calcium and that caused the calcium to lockout the potassium, I believe. Could be due to ph also.

2 Likes
#4

Calcium and potassium can also lock out magnesium and that could look like necrotic spots too.

2 Likes
#5

Thank you @HolyAngel and @BCC tough to find other pics that are so similar. Makes sense with calcium locking out p. Getting late in the run, didnt plan on more nutes at this point on a couple of these, may ride it out. Humidity just went whacky again overnight, lots of rain today so that battle is back.

2 Likes
#6

i just had something like this. i think it’s calcium, but it only looked like this on one strain (both plants) and not like this on others. instead of just getting yellowing/burn from the tip inward, i was getting burn on random spots on the leaves. it wasn’t too bad and didn’t affect yield/harvest.