P DEF???

john wishmyer

john wishmyer

Well-Known Member
noticed the tips of my dosido running a little red on the tint. also noticing a small fade on my leaves and im wondering if shes got a P deficiency what do yall think???
medium: roots organic super soil mix.
water always ph’d between 6.2 - 6.8
i usually water by weight or see a slight droop, its alot easier with these fabric pots.
 

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JohnDee

JohnDee

Well-Known Member
Hi John,
It's pretty minor...otherwise looks great. Are you adding any nutrients on top of the Roots soil?

What strain are we looking at? Heavy feeder?
JD
 
john wishmyer

john wishmyer

Well-Known Member
JohnDee said:
Hi John,
It's pretty minor...otherwise looks great. Are you adding any nutrients on top of the Roots soil?

What strain are we looking at? Heavy feeder?
JD
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strain is dosido
was top dressing some castings and alfalfa meal. definitely a heavy heavy drinker
 
JohnDee

JohnDee

Well-Known Member
john wishmyer said:
was top dressing some castings and alfalfa meal
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Worm castings can be a little hot...especially on top of an already rich soil. Maybe stop the castings and alfalfa...plant is plenty green. And maybe if you have a little guano to boost the phosphorus...can't hurt and may help. Kelp is good too (for P). Just a thought.
Cheers,
JD

PS: I am assuming you have the mycorhizzal and micro-herd aspect taken care of.
 
Michael Huntherz

Michael Huntherz

Well-Known Member
john wishmyer said:
noticed the tips of my dosido running a little red on the tint. also noticing a small fade on my leaves and im wondering if shes got a P deficiency what do yall think???
medium: roots organic super soil mix.
water always ph’d between 6.2 - 6.8
i usually water by weight or see a slight droop, its alot easier with these fabric pots.
Click to expand...
I can’t imagine a P deficiency so early in new quality soil. P requirements are actually very low for cannabis.

If you have a deficiency, and even if you don’t, I think you need to pH to 7.0. Low pH causes limited phosphorus uptake.

6.2 is too low. Anywhere 6.5 to 7.4 is fine in good soil. Shoot for a solution pH of 7.0, seriously.

Everybody is obsessed with the acidic pH, it really is not that cut and dried of a thing. I need to get my pH down in my DWC setup, but I have been running at 7.0-7.4 for a couple weeks. All the plants have been fine, but that’s a bit high for “real” hydro over long periods of time. Media, nutrient amounts and sources, lots of things can effect your optimal pH range, in soil neutral 7 is ideal, typically.
 
john wishmyer

john wishmyer

Well-Known Member
Michael Huntherz said:
I can’t imagine a P deficiency so early in new quality soil. P requirements are actually very low for cannabis.

If you have a deficiency, and even if you don’t, I think you need to pH to 7.0. Low pH causes limited phosphorus uptake.

6.2 is too low. Anywhere 6.5 to 7.4 is fine in good soil. Shoot for a solution pH of 7.0, seriously.

Everybody is obsessed with the acidic pH, it really is not that cut and dried of a thing. I need to get my pH down in my DWC setup, but I have been running at 7.0-7.4 for a couple weeks. All the plants have been fine, but that’s a bit high for “real” hydro over long periods of time. Media, nutrient amounts and sources, lots of things can effect your optimal pH range, in soil neutral 7 is ideal, typically.
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well the plant sprouted march 11th so its def been in soil for a while. i only recently transplanted it from a 2 gallon to a 7 when i noticed i needed to almost water it twice a day from how much it was drinking. As for the soil aspect i think i went a little low on the amendments as far as P, kelp meal has a .1, alfalfa meal has a 1 and i do believe need seed meal has a 2. But will probably take your advice i have always leaned closer to 6.8 will start letting it go more towards 7.0
 
john wishmyer

john wishmyer

Well-Known Member
JohnDee said:
Worm castings can be a little hot...especially on top of an already rich soil. Maybe stop the castings and alfalfa...plant is plenty green. And maybe if you have a little guano to boost the phosphorus...can't hurt and may help. Kelp is good too (for P). Just a thought.
Cheers,
JD

PS: I am assuming you have the mycorhizzal and micro-herd aspect taken care of.
Click to expand...
cheers , will probably pick up something thats heavier on P today. As for your second statement you’re correct. forgot to mention only added a small amount of castings into the mix when i transplanted i to the 7 due to the fact that i felt the original mix had N completely dialed with no signs of her being burned or hungry.
 
Michael Huntherz

Michael Huntherz

Well-Known Member
john wishmyer said:
well the plant sprouted march 11th so its def been in soil for a while. i only recently transplanted it from a 2 gallon to a 7 when i noticed i needed to almost water it twice a day from how much it was drinking. As for the soil aspect i think i went a little low on the amendments as far as P, kelp meal has a .1, alfalfa meal has a 1 and i do believe need seed meal has a 2. But will probably take your advice i have always leaned closer to 6.8 will start letting it go more towards 7.0
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Geez, 6.8 should be good, my guess was off. Best luck!
 
Logan Burke

Logan Burke

Well-Known Member
The only thing I'm seeing is the very, very beginning of nute burn, which is the tips turning brown...I think it will improve if you back off just a wee-bit!
 
john wishmyer

john wishmyer

Well-Known Member
update* still seeing her fade on a extremely low level also noticed new growth is coming in curled outwards.watered her this morning with a gallon of ro water ph’d to 6.9 anyone have a clue?
 

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JohnDee

JohnDee

Well-Known Member
john wishmyer said:
what makes u say that brother
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Well John bear with me here. I'm trying to learn how to differentiate between K and Mg deficiency.

In that second shot down...that leaf in the foreground shows clear cut interveinal fading. And elsewhere...middle shot I believe, I see some edge fading that leaves a sort of V of green in the middle.

Plus marijuana likes lots of Mg and you aren't supplementing.

So all those things together are what made me say that.
JD
 
john wishmyer

john wishmyer

Well-Known Member
JohnDee said:
Well John bear with me here. I'm trying to learn how to differentiate between K and Mg deficiency.

In that second shot down...that leaf in the foreground shows clear cut interveinal fading. And elsewhere...middle shot I believe, I see some edge fading that leaves a sort of V of green in the middle.

Plus marijuana likes lots of Mg and you aren't supplementing.

So all those things together are what made me say that.
JD
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true... i always belived most local tap contained enough Ca/Mg to keep plants nice well fed. last grow girls didnt show one sign of a def. i guess this strain could possibly be a little hungrier for it than previous strains.
 
PopTop

PopTop

Well-Known Member
I agree with Logan Burke, nitrogen abundance I always run nitrogen till leaf tips start turning brown then back off a little
 
john wishmyer

john wishmyer

Well-Known Member
PopTop said:
I agree with Logan Burke, nitrogen abundance I always run nitrogen till leaf tips start turning brown then back off a little
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that was my first thought till the tips started developing a red tint also noting that new growth is curling outward as well as fading. its beginning to fade from the edge of leaf inwards. im starting to think i have a potassium deficiency so i top dressed two tea spoons of langbeinite. hoping to see some change. its obviously mobile also because how quick its jumping from leaf to leaf including incoming growth. hoping this fixes things up would be a shame for sll the work to end up in flames
 
PopTop

PopTop

Well-Known Member
That Langbeinite is strong 0-0-22 and I've read it shouldn't be used as a top dressing because it is so strong, Rasta Roy's fool proof build your own soil recipe (my latest) only calls for 1/4 cup per cubic foot.
 
JohnDee

JohnDee

Well-Known Member
john wishmyer said:
im starting to think i have a potassium deficiency so i top dressed two tea spoons of langbeinite. hoping to see some change.
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John,
I just want to caution you. Whenever I see multiple deficiencies...I start to look at the big picture. Your soil has all the N, P, and K and probably even Mg that the plant could use. BUT it isn't getting into the plant. So at this point you need to be asking yourself why?

Something is not allowing the roots to take up the nutrients. Out of range ph, excess nutrient salt build up, root rot...all will prevent absorption.

So don't be adding more shit willy nilly till you pin down the problem. You may only make it worse.
JD
 
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Logan Burke

Logan Burke

Well-Known Member
I think JohnDee is right on the money, can you purchase a soil sample PH test kit? Any lowes or walmart will likely carry them and quite cheap, and because they aren't 'digital' they are impossible not to be innacurate and calibrate and yadda yadda...is definitely worth picking up! Then you can guarantee that PH is unrelated, narrows it down a lot!
Anyways, I'm seeing clear nute burn coupled with those leaf tips pointing straight down (generally nitrogen toxicity), and the way those leaves are folding inwards, kind of reminds me of what they refer to as 'Praying for Magnesium'...but I could be wrong there. I'm thinking something else altogether may be causing this, as JohnDee said.
 
john wishmyer

john wishmyer

Well-Known Member
PopTop said:
That Langbeinite is strong 0-0-22 and I've read it shouldn't be used as a top dressing because it is so strong, Rasta Roy's fool proof build your own soil recipe (my latest) only calls for 1/4 cup per cubic foot.
Click to expand...
i only put in a tea spoon on each wnd of the pot when i made the soil so im doubting its too abundant in the mix
 
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