Immobile Def?

[Theta]

I went from NFTG to coco nutrients (Fertmax by Cleangrow) and have been watering at a pH from 5.9-6.0 in coco.

All of my plants are doing great except one particular plant. She is showing signs of necrosis between the veins but only in brown.

I have been considering Ca, B, Zn, Mn and Iron Def. The pattern is pretty district but I am not sure what the causes is.

 

[TanzanianMagic]

I went from NFTG to coco nutrients (Fertmax by Cleangrow) and have been watering at a pH from 5.9-6.0 in coco.

All of my plants are doing great except one particular plant. She is showing signs of necrosis between the veins but only in brown.

I have been considering Ca, B, Zn, Mn and Iron Def. The pattern is pretty district but I am not sure what the causes is.

[URL=https://www.icmag.com/ic/picture.php?albumid=82604&pictureid=2015774&thumb=1]View Image[/url] [URL=https://www.icmag.com/ic/picture.php?albumid=82604&pictureid=2015775&thumb=1]View Image[/url]

I can't tell whether those are the top leaves or the middle leaves.

 

[PurplePotion]

Is this one plant perhaps exposed to more wind/air movement or close to an a/c or dehu intake or exhaust? I’ve had this happen in low RH conditions and believe Magnesium has a role to play in it, but can’t swear to that.

 

[Theta]

Top leaves

Top leaves

I can't tell whether those are the top leaves or the middle leaves.

They are top sugar leaves.

 

[Theta]

Is this one plant perhaps exposed to more wind/air movement or close to an a/c or dehu intake or exhaust? I’ve had this happen in low RH conditions and believe Magnesium has a role to play in it, but can’t swear to that.

It is the farthest from the AC and the fan is pointed away from it into a wall of the tent and the tilt is slightly away from that half of the tent. It is on the side near the tent intake. Humidity is at 60 percent with 82F during lights on.

 

[Mr. J]

That's a magnesium deficiency. The leaves in the background appear to be suffering from some other deficiency. The plant is probably underfed in general.

 

[Theta]

That's a magnesium deficiency. The leaves in the background appear to be suffering from some other deficiency. The plant is probably underfed in general.

I think you are right, I just started using CO2 and even with water at 2.0-2.4 EC going to up it to 2.6EC and double calmag dose.

 

[PurplePotion]

Wondering if pH may be playing a role as well. Checked the run off by chance?

 

[Theta]

Wondering if pH may be playing a role as well. Checked the run off by chance?

Going to test it out in a bit.

 

[TanzanianMagic]

They are top sugar leaves.

It looks like calcium deficiency/lockout.

https://www.marijuana-seeds.nl/blog/calcium-deficiency-in-marijuana

Small blotches joining up to form a large lesion.

Calcium is not mobile, so deficiency often shows up at the growing tips of the plants, and on single exposed leaves at the middle or bottom of the plant.

--

Looking at this nutrient antagonism chart, there are many nutrient which in excess can lock out calcium.

https://www.rxgreentechnologies.com/rxgt_papers/nutrient-antagonism/

Nitrogen, Potassium, Magnesium, Sodium and Ammonium Ion.

So a likely cause could be overfertilization.

 

[f-e]

Does look like a lot of Ca pics. There is a kinda Mg thing at the back. Is that red veins more under the leaf than over? P signs.

N P K Ca & Mg are commonly adjusted throughout a grow. Everything else comes lumped together in one bottle. Even if you buy the main 5 individually, the rest are still usually a trace mix. Under normal conditions, logic suggests we look at the main 5 long before the rest.

I'm out of my wheelhouse with deficiencies. There is so much contradiction in the material available to read, and much of it is transferred knowledge from other plants, that doesn't apply. I'm pedantic, and won't take anything onboard unless it sits right with me. I think we are some years away from coherent information being available, and that's not just me talking, it's in university papers.

I recently gave 3 extra Mg, 3 extra P and 3 extra K for two weeks to find my Mg problem. That is typically how I find my answers. Look, listen, then sacrifice.


Of course in some countries you can just pull off some leaves and get them to a Lab to see what is in them. Thus, see what is missing. If my country was one of them, I wouldn't even bother asking for advice or looking at the information currently available to us. I mean, my efforts to find I have a recurring Mg issue, don't tell me if the reason is because I'm short of Mg, or if it's too much K pushing it out. Which is actually an issue of cation exchange on the substrate, though it would influence what was found in the leaf. So... I'm putting in Mg, because I had an Mg problem. Is it really fixed though, or did I just cover over the problem with excess feed. I don't know, but my feed is relatively high in K.

Oh for a leaf sample. My kingdom, for a leaf sample.