Yellowing of the plant under organic soil

[JackTheGrower]

I see this often that a good sign of a correct grow is the yellowing of leaves.
This can be from two things I figure. 1. Lack of nutrients that cause the plant to pull nutrients from the leaves or 2. Natural aging of the plant.

In my situation I would need to calculate restricting the life cycle of the miro-population to prevent nitrogen from being available in the Rhizosphere to cause a nutrient availability decrease.
Or perhaps I have not let my plants age properly? I have harvested at the point I feel the curing will be nice!

Sure I cut off the application of things like fish emulsion early but how do we stop bio-activity? I see this practice more suited to liquid ion ready nutrients than organic soil.


Alright Why ?

 

[maryjohn]

depleted soil is depleted soil - microbes or not. MJ is not a legume, so all the nitrogen comes from the soil. There are other species that make a better product when grown in depleted soil - like wine grapes, for instance. The trick with MJ is you want to go from rich soil to depleted soil in one cycle. If you want to see this go wrong, see my "to feed or not to feed" thread. Because of cab issues I veged this plant for a very long time, and the soil in the tiny pot is depleted.

So I imagine if you use the dry nutes and watering only method and mess around with it a little, you can make it the right richness for what you want to do.

Another way to limit N availability to the plant is to include "too much" woody raw material. microbes in the soil will "steal" the nitrogen all around them to break down the raw material.

Another way that may be useful is to use EM. On my EM-1 instructions for houseplants, it recommends feeding more often than usual because the microbes will consume what you have. So if you use it but don't feed... Wait! that's what I did!

now microbe can come on and correct me!

 

[Mr. Greengenes]

Plants stop uptaking N from the soil when they get advanced in flowering. A little leftover N is tolerated, but too much will piss off the roots. Cannabis prefers to move the N from the leaves into the buds late in flowering rather than uptake it at the roots. That's why the leaves turn all beautiful colors and get thinner feeling. If you're using an organic container mix, you probably don't need to worry about how much N is left. As maryjohn points out, cannabis is hungry and can rip that N right out in one swell foop. As long as it's low enough that the roots don't burn and the buds don't keep stretching.

 

[VerdantGreen]

i would have thought that there would be less microbes anyway if there were less nutes in the soil because they would have less food. deciding how many nutes to add as part of the mix is tough because every plant has different needs. what i do is have a standard mix which i put pretty much everything in and usually they yellow by the time i want them to - 2-3 weeks before the end. maybe 50% will want feeding quite a bit, the rest just a couple times. organic is very forgiving i find.
i also tweek my mix to find out what happens - this last time i reduced the nitrogen (guano) and some of my plants ran out far too quickly - so now i know the original amount of N guano i was using (5g/litre of soil) was about right. lesson learnt!

 

[neongreen]

Verdant - food for microbes is sugars, protein, and micro-nutes. Inorganic nitrogen is a waste product produced by the bacteria... which is where plants get their food.

You can have all the N in your soil that is needed without stressing your plants roots as long as it's in a chelated form. That's the real trick.

Hopefully Microbeman will pop in and fill in the detail/gaps, but that's roughly what is going on in the rhizosphere.

 

[habeeb]

not sure I understand you, what are you asking

yellowing can be caused from many things:

-lack of oxygen in root zone
-nitrogen deff
-natural cycle
-being rootbound
-it could also be K, P , zinc, manganese, sulfur, iron. N is just the most common yellowing symptom
-PH off

 

[maryjohn]

Verdant - food for microbes is sugars, protein, and micro-nutes. Inorganic nitrogen is a waste product produced by the bacteria... which is where plants get their food.

The N verdant is talking about is not necessarily inorganic, and in your answer you specified proteins, all of which are made partially of N. Even in organic growing, the law of conservation of matter applies. Unless a plant is a legume, all the N it takes up originates in the soil, whether it be processed by bacteria or not. You cannot get N from C. That would be alchemy.

Further, some decomposition processes REQUIRE N. So you can have tons of N in your soil, but if there are too many processes going on that require N, there is not much left over.

While it is nice to shift focus to the microherd, it is not incorrect to think of "feeding" N to your plants. You are using a middleman, but your intentions and the result are unchanged. Kinda like the difference between understanding your car engine and being able to drive.

 

[Microbeman]

Agreed there are several reasons for yellowing leaves. If the yellowing is not related to aging/flowering 'it has been my experience' that, as MJ has alluded to, one other cause can be if there is incompletely composted organic matter (like chunks of wood, etc) the microbial life in the soil will actually end up in competition with the plant for the available N in the rhyzoshere. This is one reason it is pretty important to use totally finished (stable) compost. This is also one reason why I recommend top dressing of manures and organic materials which may be still degrading, letting the 'surface microbes' break it down and pass the nutrients down through the chain. If I end up in this situation I would try applications of humic acid and possibly EM fermentations. This is just my opinion and others may have differing stories.

 

[VerdantGreen]

Verdant - food for microbes is sugars, protein, and micro-nutes. Inorganic nitrogen is a waste product produced by the bacteria... which is where plants get their food.

You can have all the N in your soil that is needed without stressing your plants roots as long as it's in a chelated form. That's the real trick.

Hopefully Microbeman will pop in and fill in the detail/gaps, but that's roughly what is going on in the rhizosphere.

perhaps i didnt make my point so well, i realise that the microbes are what turns our organic additives into usable food for the plant - but my point was that you want to make sure the food runs low at the right point in the grow.

V.

 

[Microbeman]

Also one point that may or may not be in disagreement. It is my understanding that all organic N must be microbially processed to be uptaken by roots, as organic compounds must be in ionic form to be assimilated. There is some inference in literature that there are minimal amounts of ionic N in some organic substances but I have not read any legitimate studies. If anybody knows of such, I'd really like to read it/them. There are claims, also that there are fertilizers/substances which are microbially pre-digested and immediately available to plants but supportive literature seems lacking.

 

[maryjohn]

perhaps i didnt make my point so well, i realise that the microbes are what turns our organic additives into usable food for the plant - but my point was that you want to make sure the food runs low at the right point in the grow.

V.

And not to put words in his mouth, but this is a kind of stress imposed on the plant by the grower, not just the plant undergoing programmed senescence.

The distinction is important because it defines two distinct styles of growing.

Personally, I like to torture my plants a bit.

 

[habeeb]

Also one point that may or may not be in disagreement. It is my understanding that all organic N must be microbially processed to be uptaken by roots, as organic compounds must be in ionic form to be assimilated. There is some inference in literature that there are minimal amounts of ionic N in some organic substances but I have not read any legitimate studies. If anybody knows of such, I'd really like to read it/them. There are claims, also that there are fertilizers/substances which are microbially pre-digested and immediately available to plants but supportive literature seems lacking.

microbe, I find when I look at some products, say crabshell meal, it says water soluble which I have taken it as ready available to the plant, and then says water in-soluble I'm thinking that is what needs to be broken down by microbes ??? I would say for crabshell to be "organic"

I notice when I give my pepper plants crab shell meal the next day you can have a light green leaf turn dark green... and the overload of N can be quite damaging if not put it proper ratios.


Nitrogen (Water Soluble) ..... 4.00%
Nitrogen (Water Insoluble-Slow Release) ..... 4.00%

 

[JackTheGrower]

So then this "yellowing" style is a concept and not rooted in reality.

The concept being that the nutrient "stress" is going to make better buds?

 

[neongreen]

perhaps i didnt make my point so well, i realise that the microbes are what turns our organic additives into usable food for the plant - but my point was that you want to make sure the food runs low at the right point in the grow.

V.

I'm with you now.

You cannot get N from C.

N from C???

So then this "yellowing" style is a concept and not rooted in reality.

The concept being that the nutrient "stress" is going to make better buds?

Some people believe in it. Nails hammered through stems, "ringing", water deprevation, 24/7 darkness... lots of ways to stress plants

But the real reason most people want their plants to yellow during flower is because they think the excess nitrogen in the soil will make buds taste harsh, when in fact it's probably excess magnesium, and the leaves yellowing are a sign that the soil has become depleted of available N.

In organics, with a rich soil having the correct balance of ionic and non-ionic N-sources, keeping a plant green throughout flower is probably desirable as I understand it.

 

[jaykush]

as far as im concerned, the plant should be green for as long as possible. then cure your nugs right.

 

[habeeb]

as far as im concerned, the plant should be green for as long as possible. then cure your nugs right.

I'm with you, I have heard most the chemicals in the trich production occurs in the end, why is it good to stress the plant in that critical stage?

 

[maryjohn]

N from C???

Nitrogen from Carbon.

 

[maryjohn]

So then this "yellowing" style is a concept and not rooted in reality.

The concept being that the nutrient "stress" is going to make better buds?

Perhaps you've noticed in flowering plants across the kingdom that stressed plants often seem to work harder on reproduction. Often before a plant dies it will flower prolifically.

Why would this not also apply to MJ? Why would a constant nutrient balance, rather than a dynamic cycle, not be expected?

really though, aren't both styles are valid, depending on personal preference? That's the whole point of growing your own.

 

[relief]

not sure I understand you, what are you asking

yellowing can be caused from many things:

-lack of oxygen in root zone
-nitrogen deff
-natural cycle
-being rootbound
-it could also be K, P , zinc, manganese, sulfur, iron. N is just the most common yellowing symptom
-PH off

Bingo.

 

[JackTheGrower]

I'm with you now.




N from C???




Some people believe in it. Nails hammered through stems, "ringing", water deprevation, 24/7 darkness... lots of ways to stress plants

But the real reason most people want their plants to yellow during flower is because they think the excess nitrogen in the soil will make buds taste harsh, when in fact it's probably excess magnesium, and the leaves yellowing are a sign that the soil has become depleted of available N.

In organics, with a rich soil having the correct balance of ionic and non-ionic N-sources, keeping a plant green throughout flower is probably desirable as I understand it.

I would think to stop applying materials to "Build up" nutrients towards the end of the grow but I'm certain they will not starve..
I believe this yellowing is related to plant ready styles of feeding and build ups of these liquids in medium.. I would assume they also flush their medium to increase quality.

I'll see what I can do to ease back as far as I dare.. maybe I can improve the smoothness but it was really smooth the last time..
Where I can go that I didn't the past two grows is letting the bud go longer.. I tend to pick early because I like the up speedy high..
I will seek y'alls advice then.

There are a lot of leaves in there!