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Yellowing is not neccessarily a lack of N.

MrFista

Active member
Veteran
Today a couple of the next five leaves from the base are getting a bit yellow. OMFG MY PLANTS ARE DYING!!! I need N! :moon:

I'd like to revisit part of an earlier post as I was obviously asleep and missed it:

i think that two factors will play into this and the general N conundrum. Sativa roots tend to grow for much longer into flowering than indica roots, and because Nitrogen is made available by microbial action, then as soon as those roots stop growing their ability to take up nitrogen is going to be diminished as they deplete what is available in the existing rootzone- this can be seen easily when a plant gets rootbound, N is the first thing to go short. P on the other hand can be transported to the roots by fungal hyphae so P from the soil mass in general can be delivered to the roots by an efficient process even if the roots have stopped growing.

A good point for people growing in containers or crowding plants in when those root tips have no new ground they can't feed so they can't deliver. I was in wide bottomed 8 gallon pots before I switched to a bed, the more (room) the merrier.

Knowledge of a strain will again save headaches by knowing what size pot you need for the length of cycle you plan. Beds are great but they are a bit permanent. Not suited for all.

Doh I cut the bit from Verdants post about N transport via the water gradient. When water is present, the ion gradient will constantly be moving toward equilibrium throughout the soil. Any form of N ions will move along a gradient towards the parts of roots depleting them. Diffusion of ions through water is fairly rapid, fast enough to help the plants after a watering for sure.

Who's got a sexy senescence shot or two to brighten up the thread then? Let's see those 'starving' bitches.
 

hash head

Member
Who's got a sexy senescence shot or two to brighten up the thread then? Let's see those 'starving' bitches.
am i doing it right? :dunno:

picture.php
 

h.h.

Active member
Veteran
monsanto is evil..


agent orange... roundup gmo, suicide genes.. fucking with third world countries and everyone..


they want to own the rights to seeds all food seeds, they also like making resistant strains of weeds to roundup, and instead of farming smart.. they just make people use more water and more and more fucking roundup..

I hate them with a passion.. they are one of the true evils in this world.
Then they'll wipe out the male gene so we can't make babies. I'm talking about male plants...or am I?
 

VerdantGreen

Genetics Facilitator
Boutique Breeder
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.......:moon:.......

Who's got a sexy senescence shot or two to brighten up the thread then? Let's see those 'starving' bitches.

since you asked so nicely mr F :D

blueberry - personally i would call this P deficiency as much as i would call it senescence ;) - this was the result of an experiment to see if my Bb still foxtailed when grown hungry for N, it did. also the addition of coir to the soil made the P less available. ive run this cut a few times so can see the difference.
picture.php


this SB i can happily put down to senescence :) :dance013:
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and just when you thought it couldnt get uglier - the same goes for this NL :tiphat:
picture.php


VG
 

Microbeman

The Logical Gardener
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MM, is there a way to see organic N? or total N(organic and available)?

Sorry, I missed this.

Good question and one I don't know the full answer to. I believe there are more complex and expensive tests for detecting organic N, which involve baking and weighing soil. A good place to ask would be the Rodale Institute.
 

MrFista

Active member
Veteran
Jeepers Verdant! You're the man all right. Lookit the senescence though, do you think the third plant is starved hehe.

Amazing. Thank you.
 

guest2012y

Living with the soil
Veteran
I think this is what you're after Fista. It's strange because both parents to this cross aren't doing this at all.
picture.php
 

MrFista

Active member
Veteran
That's a pretty girl there cheeze. Are the parents indoors? Different spot or medium or lighting?

Both parents, that is interesting. Are they the strains we've previously discussed? If you have two recessive alleles coding for senescence one in each of the parents, and they both got in the recombination - whammo - senescing.

Any sisters, to see what they are doing? What about boys?

As the female is displaying senescence from both sexes of non senescing parents I think the possibility of senescence being influenced or controlled by a sex gene can be discounted (for now, but not omitted yet).

Anything helps, we'll get a clear picture of what's happening one day.
 

guest2012y

Living with the soil
Veteran
This is my H2. I've run both parents (and her) indoors a few times and outdoor this year. This was one of 3 seeds of the cross...(#2) #1 was uninteresting,I didn't keep her....and I still have the 3# seed. No males as they were a colliodial silver experiment on the female Pure Kush that produced the pollen sacs after treatment that pollenated the mother Hawaiian Sativa x Cotton Candy.
 

MrFista

Active member
Veteran
Awww. I better not be trying to decipher gene interactions then, I know nothing of DNA changes and colloidals.
 

guest2012y

Living with the soil
Veteran
Awww. I better not be trying to decipher gene interactions then, I know nothing of DNA changes and colloidals.
Kinda' weird huh.....H2 is a great indoor "cut only" result. I've since crossed H2 to PPP and BMR...who knows what those seeds hold.
 

VerdantGreen

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looks like a bit of cold weather colouring on that one too capt ?
 

MrFista

Active member
Veteran
Update: Few observations.

Be running another nitrogen test in a few days time to mark 6 weeks flowering.

The plants are senescing but only lightly underneath. Some large fans are now yellowing out and abscission is taking place. Funnily - the leaf abscission (plant forms a scar and weakens leaf-stem bond before it drops off) is taking place before all but the deep green portion of colour is removed from the leaves. The plant is dismantling something from the leaves and discarding the rest! The leaves fall on the ground a pale green and yellow mottled mosaic pattern around the veination. Rain (watering can) makes them drop off when they are ready to. Take a close peek and the petiole-stem junction points are already calloused over.

The stretch went further than I am used to with this strain. I have no idea why. The good news is the plants seem to be filling in the extra gap. Fingers crossed it will carry right on through.

One plant, dead centre, busted a sly nut when I wasn't looking, pollen dropped down underneath. Could have been a lot worse. One or two parts of one or two buds show signs of pollination, fuck all luckily. Ah, seed grows.

One phenotype has regular square or rectangular patches of cells that die in some of the bud leaves. Everything around them including the plant and leaves with these areas is the picture of health. Strange, only the one phenotype. Seen it once before in this strain.

Leap tips - these are slightly brown tinged like shots where people claim the plant has 'just the right amount of nutes' in the soil, implications are generally concerning having the max allowable nutrition before overkill, the perfect mix bla bla yada yada.

More BULLSHIT. :) :moon:

I'm not feeding these plants. There's no max ionic solutions being added, no phyto-P microbombfunkskunk bottles to be seen anywhere. The microherd is dictating the terms and has been for 6 months with almost two grows completed with no added nutes. There's no measuring cups or spoons here, no carefully contrived mixture of exact ingredients except for three years ago when I closely followed a recipe found here - then promptly added char to it.

The microherd is dictating the terms - and the plant is also dictating the terms. I know there's N in the soil and will prove that (again) shortly, but the plant chooses to remove some leaves anyway. So down bottom it appears to be hungry - up top it appears to be perfect -which is it?

I suspect I will find differing ranges of N in the soil at different parts of the plants life cycle as I continue to test, and the microbes will fix it, or lose it, as the plants needs change. I'm interested in how the N species (ions) might change over a plants cycle as well. We shall see.

The 'critical mass' of soil that MM (or CT guy, sorry fellas) suggests for a bed grow makes great sense when considering the housing the soil provides, and the services provided by it's microbial inhabitants. A critical mass of soil allows for a critical mass of organisms in the soil.

The plants have all they need, still they senesce and undergo abscission and leaf drop. Nature doing its thing, it doesn't need my interference.
 

VerdantGreen

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love your observations mr F :tiphat:

......

One phenotype has regular square or rectangular patches of cells that die in some of the bud leaves. Everything around them including the plant and leaves with these areas is the picture of health. Strange, only the one phenotype. Seen it once before in this strain.

could be on the wrong track but this sounds just like the symptoms of an eelworm infection (they are microscopic). they eat part of the leaf but are 'fenced in ' by the veins etc. never seen it in cannabis but i usually grow indoors so why would i ?


I'm not feeding these plants. There's no max ionic solutions being added, no phyto-P microbombfunkskunk bottles to be seen anywhere. The microherd is dictating the terms and has been for 6 months with almost two grows completed with no added nutes. There's no measuring cups or spoons here, no carefully contrived mixture of exact ingredients except for three years ago when I closely followed a recipe found here - then promptly added char to it.

The microherd is dictating the terms - and the plant is also dictating the terms. I know there's N in the soil and will prove that (again) shortly, but the plant chooses to remove some leaves anyway. So down bottom it appears to be hungry - up top it appears to be perfect -which is it?

I suspect I will find differing ranges of N in the soil at different parts of the plants life cycle as I continue to test, and the microbes will fix it, or lose it, as the plants needs change. I'm interested in how the N species (ions) might change over a plants cycle as well. We shall see.

The 'critical mass' of soil that MM (or CT guy, sorry fellas) suggests for a bed grow makes great sense when considering the housing the soil provides, and the services provided by it's microbial inhabitants. A critical mass of soil allows for a critical mass of organisms in the soil.

The plants have all they need, still they senesce and undergo abscission and leaf drop. Nature doing its thing, it doesn't need my interference.

the critical mass thing is crucial. i would agree with pretty much everything you say for above critical mass. below critical mass - say 3-4 gallons and below, i strongly believe that there is a few more factors, including food availability, rootspace etc that have a strong influence on how the plant finishes, especially indoors :chin:
 

MrFista

Active member
Veteran
Totally agree. Below a certain mass of soil eg pot culture - many other considerations to make. I think the more important one being root binding.

I wonder now just how little nutes are actually needed when the microherd is a large and mature beasty like mine.

Eelworm huh - this is possible. Bout a year back two feet from the base of the side of the bed rats pulled opened a bag of blood and bone and the wet ground got totally covered and saturated in it. It grew lots of pretty trichoderma a few months then settled down. This 'pollution' is close to my bed, the critters in it may have access through the soil under the wall and into my bed.

In the bed itself the topsoil has so much fungi including oysters the nematodes will likely be food for them. But access to large root systems from the very base (and the compact clay underneath) is possible. Watching real close in case it's a problem stemming from heat mildew or similar. The buds seem fine, but they smell so sickly skunk it's almost like rot anyway. Have to watch strains that smell a little like rot very closely in case the real deal arrives unnoticed.

Found a few mycorrhizal fruiting bodies yesterday (spring here) in my long grass as I was cutting it for mulch. Grabbed some soil from under alliums and rye grasses, a bunch of fruiting mushrooms - and into the worm bin they go!
 

3rdEye

Alchemical Botanist
Veteran
Great thread MrFista. This should be stickied i think. I've been following it and decided to let things just run their course in my garden instead of trying to "fix" something that ain't broke. ;) So far, so good.

I've found that there is a smell that comes from buds even if they aren't showing signs of mold/mildew yet. Hard to describe. I also think that having low hanging branches from being too close to the leaf litter/mulch or not having enough sub-canopy airmovement are also culprits for some growers.

The critical mass issue is something i am working on figuring out for myself also. I think it will be a manifold issue really. Age of the soil, microbial diversity, time of plant in same soil, type of plant, etc. Verdant Green i have many of the same questions regarding the critical mass in regards to soil.

Currently i'm running between 1/2gal to 3 gal containers, but i am thinking about stepping up to 3,5, and up for final flowering homes. Since i changed set ups i have to re-calibrate things a bit first.

Rye grass is a great place to look for mycelium. :) Especially where ever it has heavily matted.

Spring? Enjoy :) We are getting into our winter here and it gets a bit chilly where i'm at. :D
 

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