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[mustache]

Hi guys,

I’m still trying to master the nutrients. When I look up this effect on the leaves I get anything from nute lockout to light burn and nitrogen/mg deficiency. Anyone know what this is? Thanks!

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Discussion

[ZoomyCat]

Lets start with what it is *not*.

Its not light burn, How do I know? There are leaves showing signs of deficiency beside ones that have none. If it was too much light then it would be centralized *where* there is too much light and not scattered throughout the plant.

It also does *NOT* appear to be a nitrogen deficiency and the reason being is nitrogen is a mobile nutrient and this would start at the bottom of the plant and move upward.

This looks like it fits in the *Immobile* nutrient deficiency list since it appears to have started at the top of the plant and worked its way *DOWN* as there is very little deficiency and rusting on the edges of the leaves.

But before deficiency talk… I think we need to know more about the environment the plant is growing in. What are your temps and humidity, How is your watering schedule?

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[jmystro]

Potash is the issue here. Potassium is not immobile. It’s just lacking.

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[Unknown Member]

Above and beyond

Dude looked it up for you.

There’s dgc family at its finest

👏👏👏

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[jmystro]

Those charts are shit because they don’t give any context. There are many reasons for nutrient unavailability.

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[ZoomyCat]

That is why I was asking for more context ;) I said right in my post that it leads to this but more context may change the answer.

Diagnosing plants is not straight forward that is for sure! That is why I stick with the tried and true Gaia Green method. I kind of know if I have any real deficiencies I’m screwed because I don’t have the nutrients to add individually anyways.

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[jmystro]

@oldestschool Please never tell anyone to use cal-mag. Especially on a plant with a potash issue. That’s harmful advice.

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[Sasquatch]

Welp that about covers that…LOL 🙃

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[jmystro]

This is an issue with potassium. Potash deficiency affects the leaf blade edge leaving the center of the leaf green initially. Let’s go through all the reasons potassium could be lacking. It’s an element needed by the plant in higher proportion than any other throughout the plant’s entire life cycle with the exception of hydrogen, oxygen, and carbon of course. Potassium has one of the widest pH ranges so the issue is rarely that. Other elements would also be affected by pH being out of range. Damaged roots from over/under-watering is the most common issue and antagonisms from too using much calcium, magnesium or nitrogen can also lock out potash. Root damage or too much mag are the most common causes when using a complete nutrient program from a bottle or powder. Growers using organic inputs could actually run out but not a grower using soluble mineralized nutrition.

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[ZoomyCat]

Good info. Thanks for the breakdown of it.

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[mustache]

Thanks for your help guys!

I’ve been using Fox Farm Liquid plant food, and Im wondering if maybe I missed a feeding of the Big Bloom which mainly has phosphate and potash.

My Temp is about 76 and humdity is 50% which puts my VPD at 1.5. Do you think its off? All plants are at week 6 of flower. Im growing both Wedding Cake and Durban Poison, and the wedding cake seems like its suffering more, and the plant in the picture is defintely the worst.

So when trying to equilize the nutrient deficiency should I just go with the “heavy feeding” listed on the bottle? Should the plants with visible deficiency get more, or they all get the same?

As for watering I’ve been trying to dry back them some, and letting the pot get to about 25% or so before watering. So far its been about 1/2 Gallon every 2-3 days.

Thanks guys!!

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