Yellowing of upper leaves

Hi all! I have some yellowing on the upper leaves of my Afghan Autoflower (she’s 8 weeks old). I post pics because the yellowing pattern is kinda odd to me and I’m hoping to get a sense of what’s going on.


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Doo you have pH readings and ppm reading my gut says she’s getting hungry

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Looks like normal leaf variegation. She looks healthy, but like @Dclark says, it’s always a good idea to monitor runoff pH and PPM.

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That’s was my second bet lol

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pH is within normal range; not sure about ppm. She’s been flowering for about 3 weeks so I’m using bloom nutes with an NPK of 2-8-4 (1 tsp per gal of pH balanced water).

I would get and use a good cannabis fertilizer. Cannabis has unique needs that aren’t satisfied with ordinary fertilizers. Fox Farm products, Jack’s 321, General Hydroponics, and Advanced Nutrients all make good products.

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Yup I’ve been using Fox Farm’s trio! The Tiger Bloom is the 2-8-4 and I’ve also been using a little Big Bloom. No Grow Big in the past week or so…I weaned out the nitrogen based on some research I did on here.

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I usually don’t weigh in on nutrient deficiency and the such, due to my limited knowledge, and they are so confusing.
But the only time that I have seen that weird looking psoriasis type patches, (with the clean dividing lines between the dark and light patches), it was caused by light stress. It is hard to tell from the pictures, but it looks like there may be some canoeing, also another sign of too much light. I get this when my seedling go from the clone tent with 2 small fluorescents to the big tent with the brighter LED. But I had this develop in the top of my larger tent suddenly. This was due to the plants growing a little too close to the light, and while conditions in tent changed just enough to put the VPD over the edge.
Phosphorus deficiency looks similar, but I don’t see any purple stems that usually comes with this deficiency.

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Ahhh yup, I was thinking it could be due to light stress because admittedly the light was pretty close. I just brought the light up so the distance is about 18" now. Hopefully that’ll help. Thanks so much for the advice!

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Beastie Bloomz is the P, K supplement to use in flower.

Be careful of the FF grow schedules as most I’ve seen are in U.K. scale or 700 scale. If you are using U.S. scale (500) then you will be overfeeding. Keep your mix TDS at no more than 1,100 ppm or so. Too much will reduce yields (as is too little lol).

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Cool, moving the light from 12 to 18 inches, and increasing air movement in the tent did the trick for me. The damaged leaves continue to grow, but the damage will stay and turn brown. The new growth should start to look fine. If we swerved into the right direction here.

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