Hemp (Cannabis sativa L) tissue nutrient analysis data

[spurr]

@ Tester,

Thanks for that great post, for the next graph and for correcting my math; also thanks for providing the more accurate data for N, P2O5 and K2O.

About the Lucas formula, etc., I used 1 liter containers to find the data about GH3's mix, my mix and Lucas's mix from GH ferts.

To anyone not familiar with Lucas's formula, he suggested it to be used all the way from veg to harvest. I also use my mix from veg to harvest.

 

[spurr]

"For example, all of the plants grown on soil with less than 100 ppm of extractable P2O5 contained less than 8,000 ppm {Delta}9THC."

I would infer from the above sentence that less than 100 ppm of P2O5 reduced THC content. The following sentence is also thought provoking:

"Uptake of K was positively correlated with extractable K.2O across all treatment levels (r=0.40**), but was negatively correlated with tissue yield (r=--0.36"*)."

The earlier AN study and accompanying bar graphs referred to by Carl Carlson would ostensibly demonstrate a much higher need for K in flowering. However, the above quote indicates that increasing K increases uptake of K but decreases yield. Perhaps the AN study testing higher K supplementation in flowering merely reflects the increased uptake of K in tissue analysis and nothing else. Yield and potency may still be lowered in a high K and low P scenario. I am only hypothesizing based on this one abstract but I do find it quite interesting, as there is very little in the scientific literature that looks directly at what this particular study appears to demonstrate.

I agree the study would be nice to read, and your speculation about the abstract is valid. I found the study again and should have it in full text soon, at least by after the holiday. The other paper I am getting is "Mineral nutrition of Cannabis sativa L.".

Regarding H3ad's formula and results, he tweaked his formula about halfway through his thread by increasing the GH Bloom to 12 ml/gal for a portion of flowering. He also uses little if any epsom anymore (occasionally 1/2 gram/gal). The 6/12 formula gives the following profile:


N: 97
P: 79
K: 137
Mg: 55

Thanks for that, I was unaware he changed his mix.

I used his formula for a while (I grow in coco) and found it a bit too low in P and K once 12/12 was initiated. My results improved rather dramatically by increasing the bloom upon initiation of 12/12 and keeping it higher throughout the flowering cycle. Whether the plants are benefiting from the higher K alone or the higher P as well is not clear. However, the higher P seems not to result in any negative effects. Also, there are plenty of very good growers on this site getting excellent results using nothing but GH Maxibloom, which is fairly high in P and and K and pretty low in N.

In regard to P levels, I hope it didn't seem like I was inferring high P levels are bad or hinder cannabis growth. My reason for using reduced P is to keep P in what I believe to be the low-end of the sufficient range, and to not over-apply P without need or benefit. Plants self-regulate uptake of P, and they also 'store' excess P in tissue if need be. So using P levels of ~100 ppm isn't bad, but IMO it isn't needed either.

I am currently running a combination of Canna Coco A&B plus GH Bloom and Canna PK 13/14. My bloom formula is 9 ml/gal A&B plus 5 ml/gal bloom and 1ml/gal PK 13/14. This gives the following:

N: 138
P: 97
K: 154
Mg: 52
Ca: 126

I am getting truly excellent results with this profile.

Great, love to see growers doing well!

The bottom line for me is that I don't think the jury is in yet on the P question when it comes to container grown cannabis and the goal of higher yields in conjunction with maximum potency.

I agree, that said, current and past scientific evidence points to lower P needs vs higher P needs. Granted, we haven't read those two studies we are discussing in full text yet, so I agree 100%: the jury is still out.

 

[spurr]

@ all,

I will be getting those two last studies I cited* sometime in the next two weeks, as I have some free time. Sorry for being slow, the holidays and such took me off-line for a bit.

Also, see this post for a pic of plants in early flowering getting sufficient P of 40 ppm: https://www.icmag.com/ic/showpost.php?p=4138942&postcount=46

* studies I will get:

1. "Mineral nutrition of Cannabis sativa L."
S. Landi
Journal of Plant Nutrition, Volume 20, Issue 2 & 3 February 1997 , pages 311 - 326


2. "Responses of Greenhouse-grown Cannabis sativa L. To Nitrogen, Phosphorus, and Potassium"
C. B. Coffman and W. A. Gentner
Published in Agron J 69:832-836 (1977)

 

[spurr]

@ all:

I just wanted to let people know I have the following studies in full text, so no need for anyone to buy them. After I finish reviewing them, and making some notes, I will upload them here, probably tomorrow at some point. The first two I already referenced in this thread but not in full text, and I also found a few other relevant studies, all in full text

Spoiler Alert...Spoiler Alert...Spoiler Alert...Spoiler Alert...

• The second study found P level positively effects (correlated to) both THC and CBD, considerably to total THC. And that P is positively correlated to growth (height), as has been pointed out in this thread; re high P during veg and pre-flowering is not a good idea for short/stout plants with tight internodal length. That is only from my very quick scanning of the paper, so don't hold me to that spoiler; there are also results relevant to Mg, Ca, N, K, etc. I will review that paper and the others, thoroughly, tomorrow. However, suffice it to say there seems to be evidence that P and Pi level is positively correlated to quantity of THC and CBD. A (rather weak) hypothesis put forth in the paper (see quote below) is that P might be used for THC and CBD synthesis. If that hypothesis is true, it seems like P might be used for CBG synthesis because current evidence finds CBG is the precursor for both THC and CBD. Thus, I think I may make a fertilizer mix with increased P (i.e., Pi) for post pre-flowering to allow for most THC and CBD, but not increase stretch during pre-flowering and veg. I believe that study did not looked at flowered plants, age was about a month and half, from my quick scanning of the paper...

...The biochemical mechanisms responsible for synthesis of cannabinoids are not clearly understood; therefore, we cannot yet explain how previously discussed elements affect cannabinoid production. Phosphorus may be involved in cannabinoid biosynthesis via the interaction of geraniol phosphate and olivetol (Mechoulam, 1973). The other elements may affect related enzymatic reactions...

Side note: I do not grow conventionally as a rule, I prefer biological organics, by far, even though a grower losses a degree of control over fertilizer inputs.

​

1."Mineral nutrition of Cannabis sativa L."
S. Landi
Journal of Plant Nutrition, Volume 20, issue 2 & 3, pp. 331-327 (1997)


2. "Responses of greenhouse-grown Cannabis sativa L. to nitrogen, phosphorus, and potassium"
C. B. Coffman and W. A. Gentner
Agronomy Journal, vol. 69, pp. 832-836 (1977)


3. "Cannabinoid profile and elemental uptake of Cannabis sativa L. as influenced by soil characteristics"
C.B. Coffman and W.A. Gentne
Agronomy Journal, vol. 67, pp. 491-497 July-August (1975)


4. "Effects of fertilizers on yields and breaking strengths of American hemp, Cannabis sativa"
Howerd V. Jordan, A.L. Lang and George H. Enfield
Journal of the American Society of Agronomy (1947)

 

[trichrider]

would love to see your papers' text. thank you for posting relevant articles and in such abundance. K+

 

[Avenger]

@ all:

I just wanted to let people know I have the following studies in full text, so no need for anyone to buy them. After I finish reviewing them, and making some notes, I will upload them here, probably tomorrow at some point. The first two I already referenced in this thread but not in full text, and I also found a few other relevant studies, all in full text

Spoiler Alert...Spoiler Alert...Spoiler Alert...Spoiler Alert...

• The second study found P level positively effects (correlated to) both THC and CBD, considerably to total THC. And that P is positively correlated to growth (height), as has been pointed out in this thread; re high P during veg and pre-flowering is not a good idea for short/stout plants with tight internodal length. That is only from my very quick scanning of the paper, so don't hold me to that spoiler; there are also results relevant to Mg, Ca, N, K, etc. I will review that paper and the others, thoroughly, tomorrow. However, suffice it to say there seems to be evidence that P and Pi level is positively correlated to quantity of THC and CBD. A (rather weak) hypothesis put forth in the paper (see quote below) is that P might be used for THC and CBD synthesis. If that hypothesis is true, it seems like P might be used for CBG synthesis because current evidence finds CBG is the precursor for both THC and CBD. Thus, I think I may make a fertilizer mix with increased P (i.e., Pi) for post pre-flowering to allow for most THC and CBD, but not increase stretch during pre-flowering and veg. I believe that study did not looked at flowered plants, age was about a month and half, from my quick scanning of the paper...

Side note: I do not grow conventionally as a rule, I prefer biological organics, by far, even though a grower losses a degree of control over fertilizer inputs.

​

1."Mineral nutrition of Cannabis sativa L."
S. Landi
Journal of Plant Nutrition, Volume 20, issue 2 & 3, pp. 331-327 (1997)


2. "Responses of greenhouse-grown Cannabis sativa L. to nitrogen, phosphorus, and potassium"
C. B. Coffman and W. A. Gentner
Agronomy Journal, vol. 69, pp. 832-836 (1977)


3. "Cannabinoid profile and elemental uptake of Cannabis sativa L. as influenced by soil characteristics"
C.B. Coffman and W.A. Gentne
Agronomy Journal, vol. 67, pp. 491-497 July-August (1975)


4. "Effects of fertilizers on yields and breaking strengths of American hemp, Cannabis sativa"
Howerd V. Jordan, A.L. Lang and George H. Enfield
Journal of the American Society of Agronomy (1947)

come on man

 

[spurr]

would love to see your papers' text. thank you for posting relevant articles and in such abundance. K+

Your wish is my command, my friend; the same goes for Avenger. Hope both of you find these of use

come on man

Sorry, I've been slow getting to those papers.


I will upload them to this post and save my commentary on them, of any potential issues with the results or methodology, until tomorrow. I would love to read both of yours, and others, opinions on the results, potential flaws in methodology, etc., of the studies...

The first and third studies appear to be more about identification of the geographical location of the plants, than about ideal fertilizer for cananbis; but I haven't read them thoroughly, yet.

The second study seems most relevant for us in terms of P, mostly because it's conducted via greenhouse grown cannabis verses outdoor in possibly poor soil.

I have to remove some identifying info from the first study so I won't upload it for maybe a half an hour. The software I did use to edit the study also took out some data from a table so I have to re-do the editing.

I looked over the references in a couple of the studies, and found other studies I would like to read. I will get those other studies next week.

Oh yea, some of the info is old/incorrect, like in the third study a hypothesis is put fourth that THC comes from CBD (as if CBD is a precursor for THC). However, current scientific evidence finds that is not the case, CBG is the precursor for both CBD and THC.

If either of you find studies in the references of any of those studies, that you would like to read, add them to my thread for full text papers (link) in the science sub forum, and I should be able to get them.

Lastly, I think I am going to ask Oldpink to move this thread to the science sub-forum; what do both of you think? Good idea? Or no?

 

[spurr]

DynaGro's ProTekt label's says:

• 3.7% K2O
• 7.8% SiO2 (=3.646% Si calculated with the molar mass calc)

1.2 g/ml specific gravity according to MSDS


2.5ml ProTekt per gallon:

• 29.3 K2O
• (24.3 K)
• 61.83 SiO2
• (28.9 Si) (instead of 56)

Hey Tester,

I was looking over a website YosemitySam(sp?) suggested as his source for fertilizer salts, and I noticed a claim made about ProTeKt. I believe what you provided above is correct, but I wonder why that site lists 1 ml of ProTekt in one gallon of water giving 21 ppm of Si and 8 ppm of K (link).

I am buying the Nutron 2000+ software this week, PM me if you want a copy (link to software info).

 

[spurr]

"Mineral nutrition of Cannabis sativa L."
S. Landi
Journal of Plant Nutrition, Volume 20, issue 2 & 3, pp. 331-327 (1997)

 

[habeeb]

thanks spurr..

appreciate it

 

[spurr]

You are very welcome, glad to help

 

[tester]

Hey Tester,

I was looking over a website YosemitySam(sp?) suggested as his source for fertilizer salts, and I noticed a claim made about ProTeKt. I believe what you provided above is correct, but I wonder why that site lists 1 ml of ProTekt in one gallon of water giving 21 ppm of Si and 8 ppm of K (link).

I am buying the Nutron 2000+ software this week, PM me if you want a copy (link to software info).

The problem is that they refer to SiO2 with the name "silicon" which should mean Si, not SiO2 (= silicon dioxide).

1 ml of ProTekt in one gallon of water giving 21 ppm of SiO2 and 8 ppm of K

21ppm of SiO2 is 10ppm Si

Dynagro does the same mistake on the label, listing "Silicon (SiO2) = 7.8%"

According to the MSDS its a 24.9% Potassium silicate solution.

 

[tester]

These charts were extracted from the documents and studies posted above.

"Mineral nutrition of Cannabis sativa L."
(Uploaded by Spurr)

• Notice the difference in the level of Ca, the flowers contains much less Ca than the leaves.
• Also notice the difference in the level of Zn and Fe, Mn.

From AN's "The Great Phosphorus Myth Exposed!" (and the video)

Lot's of questions:

• Feeding schedule (I'm sure the plants was feed with AN nutrients but don't know anything else)
• Where are the tissues from? (Always from the same plant, or different plants, clones...)
• What part of the plants are the tissues from?
• How big was the tissue sample? (from the sample weights I assume it was a single leaf but it still can be a generalized part of the whole sample)

Because these questions are unanswered nothing can be taken to certain.

3 strains were tested (Hash Plant (HP), Berlin (B), White Rhino(WR) ), they took a sample every week until harvest.
Charts on the left are for Macro elements, the right ones for Micro elements.
Green columns stands for samples taken on week 1 (Vegetative stage) the brown columns are for the weeks in the flowering stage. Darker brown means we are further into flower, the last week is the darkest.

Macros:

• Level of P was raising towards the end of flowering in every sample
• There is a big drop in the level of K on the last week in HP and B but not in WR.
• The level of N is higher on the last week as was on the week before (B, WR)
• I wonder if they got flushed? The tests were done in 2003.
• This is where I stop because it's completely contradictory, some elements were raising while others sinking on one plant, doing the opposite on the other. Might be because of different growing conditions.

Micros:

• Si is very high, even higher than Fe. (Does it have any negative health effects?)
• Lots of peaks in Si within WR.
• Level of Mn and Fe is raising towards the end of flowering in HP and B, but sinking in WR.

This is from Fatman's analysis

• Notice the drop in the level of Ca in the flowering plants. This correlates with the findings of the other tissue analysises

This is a quick one that shows the optimum level of P (based on a table from Hemp diseases and Pests (pic attached)) and an other diagram already linked in this thread.
https://www.icmag.com/ic/showpost.php?p=3952725&postcount=38

Albeit these are guidelines for hemp, it's still interesting to see the differences.

 

[habeeb]

^ alot of info there.. busy so cant comment on that

but for fatman, if you look through all his posts ( I did one weekend, and saved all his info , believe it was 40 pages of small print.. his knowledge is top, but his attitude another story.. )

 

[YosemiteSam]

The calcium levels in leaves vs bud is something i have become fascinated by. Ca moves based on how well the plant is transpiring...leaves transpire way better than bud so, imo, they are going to end up with more Ca. The data itself confirms leaves have more although it does not explain why.

The question I have is if the buds actually need less Ca or just end up with less because of the way Ca moves in the plant.

I have a small grow where I am foliar feeding Ca (spraying it right on the buds) all of the way through flower. I will see what I see.

 

[spurr]

I just wanted to thank oldpink, or whomever moved this thread into the science subforum.

 

[tester]

But sadly the attachments from my last post are missing.

 

[spurr]

Which ones? I see many attachments, didn't notice you most recent post until right now. I am off to read your post, it looks good

 

[tester]

two pics missing I can see the broken image icons, these were uploaded as attachments to icmag

edit: nevermind, uploaded the missing images again and edited the original post

 

[spurr]

Si is very high, even higher than Fe. (Does it have any negative health effects?)

Not that I am aware, Si is considered by some plant physiologists to be a maconutrient, albeit a secondary macro, on par with Mg in terms of ppm...

One main reason I like to use at least 30 ppm Si (at most 60 ppm Si) aside from increasing strength of cell walls, defense against biotic and abiotic stress (ex. powdery mildew and element toxicity, respectively), and transpiration issues (ex. water use efficiency), etc., is trichomes are comprised of Si to decent degree:


"Trichomes of Cannabis sativa L. (Cannabaceae)"
P. Dayanandan and Peter B. Kaufman
American Journal of Botany
Vol. 63, No. 5 (May - Jun., 1976), pp. 578-591

The diversity of non-glandular and glandular hairs of Cannabis sativa L. (marihuana) are described by scanning electron microscopy. The non-glandular hairs are of two major types, as distinguished by size differences and locations, and all of them are highly silicified.

Silicified = "Convert into or impregnate with silica." (cite)​

Also, see:

Chap 5: Silicon deposition in higher plants
Studies in Plant Science
A.G. Sangstera, M.J. Hodsonb and H.J. Tubb
Volume 8, 2001, Pages 85-113
Silicon in Agriculture


"The Mineral Nutrition of Higher Plants"
David T. Clarkson
Ann. Rev. Plant Physiol. (1980) 31, pp. 239-298

I uploaded the full 60 page text for you. Link to German file host site, turn off Java-Script for no ads; passphrase is "mineralstudy" (without quotes).

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