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Help: Yellowing Edges. (Zinc or Manganese Deficiency)

Jutachi

Active member
I already flushed the crap out of them shortly after I started this thread. I've added fresh topdressing also so if I did just let it ride and hope for the best it probably would get better on it's own now but I wouldn't learn as much.



Hey @Jutachi do you have any links? I'd like to check out what you're talking about.
here ya go, plenty of info in there to read up on
 

PadawanWarrior

Well-known member
Well it's definitely not an abundance of P. Here's the results after about 2 hours.

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Here's another test.

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Tested the calcium carbonate level with my Taylor kit. I reads 120 ppm calcium carbonate.

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One more pH test using the Taylor kit. It reads about 7.0-7.2. Not sure which ones to trust. My Bluelab and the well test kit read around 6 but the Rapidtest and the Taylor both read around 7.

WIN_20240514_16_52_20_Pro.jpg
 
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PadawanWarrior

Well-known member
nifty gear, where did you get it all...no grow shops near me to browse...
I got the first kit that tests pH and NPK for like $12 at a grow shop when I started. And the test kit I bought for my well water on Amazon. But I just looked and both are available at Amazon.

WIN_20240514_16_30_03_Pro.jpg
 

PadawanWarrior

Well-known member
What all does that well kit test for? Ph under 8 means bicarbonates usually. Curious about mg and na levels too.
The well test kit tests for a bunch of minerals and it also comes with a chloriform test. If you zoom in you can see all it tests for. I did test calcium carbonate and it came out at 120 ppm. I wish I had one that tested Mg, Na, and Ca too. I haven't seen one that tests for that yet.
 

jackspratt61

Active member
The well test kit tests for a bunch of minerals and it also comes with a chloriform test. If you zoom in you can see all it tests for. I did test calcium carbonate and it came out at 120 ppm. I wish I had one that tested Mg, Na, and Ca too. I haven't seen one that tests for that yet.
Does it test for bicarbonates. Zooming in doesn't help with my bad eyes.
 

PadawanWarrior

Well-known member
Does it test for bicarbonates. Zooming in doesn't help with my bad eyes.
Not sure. It just says calcium carbonate. But I just used the Taylor kit to test for Alkalinity which from what I understand should also be the test for bicarbonates. The reading was 50 ppm alkalinity so I'm assuming that's 50 ppm bicarbonates but I could be wrong.

Here's another pic of what the well water test tests for.

WIN_20240514_17_10_51_Pro.jpg
 

Jutachi

Active member
From those test, it appears you're low on P and K. And you probably need to up the calcium a bit as well once you start pushing the P and K levels. You said you are in organic soil so whatever ammendment you add will take time to work and the plants will suffer in the meantime, but id top some dr earth flower girl and some compost and give it a bit. A second option Id suggest is transplanting into a new mix that is good to go and reammend that current mix and give it time to cook up hit it with some teas and good quality compost, EWC etc. Those plants are hungry and stressed. Im not sure how well leeching the soil with bottled organic nutrition would work, but ideally you'd want everything in the soil the plant needs from the jump, so you wouldnt have to do that. Definitely check your water too.

"An alkalinity test measures the level of bicarbonates, carbonates, and hydroxides in water and test results are generally expressed as "ppm of calcium carbonate (CaCO3)". The desirable range for irrigation water is 0 to 100 ppm calcium carbonate. Levels between 30 and 60 ppm are considered optimum for most plants.

Irrigation water tests should always include both pH and alkalinity tests. A pH test by itself is not an indication of alkalinity. Water with high alkalinity (i.e., high levels of bicarbonates or carbonates) always has a pH value ÷7 or above, but water with high pH doesn't always have high alkalinity. This is important because high alkalinity exerts the most significant effects on growing medium fertility and plant nutrition."

"To ideally grow out a plant, you never want to have a K deficiency, which by the way is not very common until the plant kicks into heavy growth, and even then, one should proceed with caution as ideally one would be increasing and increasing quantities throughout the veg cycle. Here is a major issue that needs to be confronted and is critical to understanding how to push growth/flower/fruit.

The plant can never be without potassium. Ideally, if Calcium was high, one could really push potassium heavy and max out production. But not up front. That would be fatal. At the right moment in time, ideally we would push quantities past daily consumption rates to start raising the level or percentage of what is K in the CEC. This is a lot of potassium. Much more than a seedling would ever tolerate. Pushing hard. Why? The more K you can get in, the more you get out. The constraint to K uptake though, is having enough Ca to handle it. If I start with low Ca and I push K, I could never push it to where I could really max out the production of plant mass. Realize that potassium can be taken up from around the soil by osmosis (concentrations) and that the area right around the root can become void of potassium and this is why the potassium has to nearly be constant, in incremental and exponential quantities. However, when you want to flower, you push K down heavily with Ca, so that all the new roots that need to pop below will get what they need and not be short of Ca at this magic moment in time. ~slownickel"
 
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PadawanWarrior

Well-known member
Still working on it. Today I gave it a tiny bit of GH Flora Trio. I've never cheated this bad, but I figured I'd try it. It's not like it's gonna kill the soil. I also poked a chopstick in the soil a bunch of times and then added a little over 1/8 cup 0-7-0 Indonesian bat guano and some Craft Blend. My thought was to get some of the P closer to the roots. I also defoliated a bit.

Here's a couple of her daughters in 15's at 1 week.

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WIN_20240515_20_12_58_Pro.jpg
 

PadawanWarrior

Well-known member
Looking a little bit better but has a ways to go. If I can get her healthy I'll put her into flower again. I have a feeling that yellowing was Mg deficiency but can't say for sure. I'm prepared for next time if it happens again.

WIN_20240517_12_01_16_Pro.jpg
 

jackspratt61

Active member
Looking a little bit better but has a ways to go. If I can get her healthy I'll put her into flower again. I have a feeling that yellowing was Mg deficiency but can't say for sure. I'm prepared for next time if it happens again.

View attachment 19004119
Ca/P balance getting better. Dr Earth + 0-7-0 making the difference. Ca is job #1 and P #2. You will require less k and mg when these are balanced.
 

thandee

Active member
Hi PW ,what i see there from my personal experience on outdoor plants in general not only cannabis,this is iron deficiency....or secondary rore microelements...you have to give them food with all of those and the plants will recover... outdoor needs 1-2 months to see improvement...but plants continue to flowering slower....but in general i don't know what you were doing with the plants from the start...you know better your Job there!!!;)
 

PadawanWarrior

Well-known member
Hi PW ,what i see there from my personal experience on outdoor plants in general not only cannabis,this is iron deficiency....or secondary rore microelements...you have to give them food with all of those and the plants will recover... outdoor needs 1-2 months to see improvement...but plants continue to flowering slower....but in general i don't know what you were doing with the plants from the start...you know better your Job there!!!;)
I thought Fe deficiency started by the stem and went out towards the leaf edges. I'm leaning to it being Mg or Zn deficiency but that's just what I'm guessing.

sddefault.jpg
 

PadawanWarrior

Well-known member
I prefer pH 6.2 to 6.8 and know pH 7 or higher will result in some deficiencies eventually.
My soil is usually around 6.3. I tested this when the thing first started yellowing and it came out at 6.3, then I tested it again a week later and I got 5.9, so I raised it with a little pH up. Then I tested it with a few different kits and got anywhere from 6-7 so I think I need to calibrate my Bluelab and check it again.
 

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