The myth, of the high P myth?

[analogue]

I have maintained 60 ppm Phosphorus since the start of 12/12.

These are Double Strawberry Diesels at day 46.

 

[tester]

Yields on 15 lights were within a pound of each other between the 40ppm grow and the one that went up to 90. Genetics were not exactly the same so no way is a pound significant.

Quality did improve though.

So the plants compared for quality and trichome production were not clones?
Were they seeds?
Different strains?

 

[Storm Shadow]

http://www.cabdirect.org/abstracts/19720705850.html;jsessionid=CA9B5D4CEA8CABFBE385ED6E9BAAD87D

Abstract

Uptake of N and K by hemp plants reached a peak 20-25 days after sowing, whereas P uptake was almost uniform throughout growth and tended to increase towards maturity. Average yield of air-dry stems, 11.25 t/ha for both hemp. CV., was unaffected by plant population within the range 100-150 plants/m2. Highest yields were obtained by incorporating 100 kg N/ha before sowing and applying a further 20 kg N/ha 20-25 days after emergence. C-PVK-21 contained 16.23% fibre and yielded 1.82 t fibre/ha whereas F-1203 contained 15.01% fibre and yielded 1.63 t fibre/ha. On average, male plants contained 16.99% fibre, female plants 14.02%.

 

[Storm Shadow]

http://www.actahort.org/members/showpdf?booknrarnr=434_9

TOMATO GROWTH IN CALCAREOUS SOILS IN RELATION TO FORMS AND LEVELS OF SOME MACRO- AND MICRONUTRIENTS

Authors: A.-S. S. Ismail, Ahmed M. Eissa, A.S. El-Beltagy, A.F. Abou HadidAbstract:
A pot experiment was carried out using two surface soil samples from north-western coast of Egypt, to study the effect of different levels and forms of phosphorus, iron and zinc on their availability in soils was as well as dry matter yield of vegetative growth and the total uptake of such nutrients by tomato plants. Obtained data reveal that increasing Fe or Zn levels either mineral or chelated form as well as P-level tended to increase their residual values in the studied soils. The highest residual values being obtained were by application of 100 ppm P + 40 ppm Fe as FeSO4 and 100 ppm P + 20 ppm ZnSO4. Therefore, application of Fe or Zn in chelated form resulted in low residual amount in soils and increased their uptake by plant growth. Concerning tomato seedlings, the dry matter yield is highly increased by application of tri-combination P x Fe x Zn in comparison with application of mono- or di treatments. Phosphorus concentration and its total uptake highly increased by mono-application of phosphorus. Moreover, applying high level of 100 ppm P in combination with Fe and Zn decreased the concentration and total uptake of Fe and Zn in those plants grown in Sedi-Henish area. Concerning P/Fe and P/Zn ratios in tomato plants were highly depended on the nutrient level and form as well as the optimum combinations between them.

 

[Storm Shadow]

https://www.crops.org/publications/aj/abstracts/69/5/AJ0690050832

Responses of Greenhouse-grown Cannabis sativa L. to Nitrogen, Phosphorus, and Potassium1

1. C. B. Coffman and
2. W. A. Gentner

Abstract

Growers of illegal Cannabis sativa L. use various cultural practices to maximize crop production. The objective of this study was to evaluate the morphological and biochemical responses of greenhouse grown C. sativa to soil incorporated N, P, and K as they reflect the geographical origin of Cannabis derivatives. Fertilizers were blended with Ap horizon soil from a Gilpin silt loam before placement in 12-cm pots. NH4NO3-N was applied at 0, 25, and 125 ppm. Phosphorus and K from super-phosphate and KCI, respectively, were applied at 0, 50, and 150 ppm. Forty-five-day-old anthesic Cannabis plants were harvested and combined leaf and flower tissues were analyzed for cannabidiol (CBD) and Δg-tetrahydrocanna-binol (Δ9THC). Nine essential elements were also measured in plant tissue. Plant growth, tissue yield, and concentration of CBD and Δ9THC were positively correlated with extractable P2O5 (p < 0.01). Phosphorus concentrations in tissue were similarly related to yield of dry matter and cannabinoid concentrations. 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"*). Growth and tissue yields were negatively related to total plant N (p< 0.01). Levels of extractable P2O5, Mn, B, and Mg were associated with specific concentration ranges for several plant elements plus Δ9THC. Thus, it was possible to partially characterize a soil by tissue analysis. For example, all of the plants grown on soil with less than 100 ppm of extractable P2O5 contained less than 8,000 ppm Δ9THC. Usefulness of such relationships will be dependent upon extensive evaluation of Cannabis on different soils under various cultural conditions. At this time, the reliability required for determination of origin of Canabis derivatives via chemical analysis does not exist when only essential elements and cannabinoids are considered.

 

[YosemiteSam]

So the plants compared for quality and trichome production were not clones?
Were they seeds?
Different strains?

They were all clones. It was not the exact same line up both grows but there was considerable overlap. In that room we run nothing but clones of proven cuts. We have a small room for seed runs, selection, etc.

Plants grown at 90 ppm P in both grows...clones from the same stock plants...were noticeably more triched out.

From a purely statistical point of view maybe I cannot say with high confidence anything about the yield...but based on my experience with all of the plants involved I do not think there is any difference in yield.

edit...nice looking plants analog. They should be so tasty.

 

[DonkDBZ]

I was plugging different companys ferts in the cannastat calculator. f'in Advanced Sensi Bloom A/B 10ml gallon is

152N 66P 252K 106Ca 21Mg

my friend was on a budget last ran just there a/b and some sweet and said he add a much better run then when he used all there additives

 

[DonkDBZ]

I will say this for SS. If you have ever grown Larry OG x anything you will know those are excellent looking buds. That stuff just flat does not grow what anyone would call trophy colas. So I am giving you a big ol well done SS. There is no question that Spurr formula is a good one...the only question is if it is the best one or not.

What I found...I think...is that P just flat does not influence yield much at all. My plan is to stick to 40 ppm through stretch. But here is where I disagree SS. I think bumping it after stretch, at least for a couple of weeks, increased trichome production quite a bit.

That is based on actually trying it, not on a study.

I also found that while a K:Ca:Mg ratio of 4:2:1 works pretty damn good it does end up showing some Ca and/or Mg deficiencies late in the cycle. This time around I am going to hold most other things equal but go to a 3:2:1 ratio for those things. We will see what we see.

The plant I have been posting, the ISS, is harvested. It is not dry yet but it is gonna be somewhere between 2 and 3 pounds. It is a 15 light, 15 plant setup...so should be at least 1 gram per watt or more.

But...it is an ISS, not an OG...so comparison really don't mean shit.

Anyways...next go around my peak will be...125-90-250-166-83-98...N-P-K-Ca-Mg-SiO2.

My thinking is that the healthier you keep the plant all of the way to the end the more you let it express its genetic potential. I failed that this time with the Ca/Mg problem. Live and learn.

How much sulfer would be too much? using cns-17, sweet, and big bud. You could get really close to those numbers but the sulfer is at 125

 

[Overthinker]

Little update on my progress with the new feed regimen. Stretch continues to be more than well controlled. today is day18 and I am surprised by how nicely everything is stacking. I am very impressed with the general nute profile philosophy coming out of this thread.

I was plugging different companys ferts in the cannastat calculator. f'in Advanced Sensi Bloom A/B 10ml gallon is

152N 66P 252K 106Ca 21Mg

my friend was on a budget last ran just there a/b and some sweet and said he add a much better run then when he used all there additives

DonkDBZ,
I have been goofin' around the same way trying to get some good profiles out of the shelves full of bottles of products I have given up on. Trying to see if I can find a way to make good use of foolish purchases of the past. That seems to be a decent profile there, toss in a little cal-mag/epsoms and it would be pretty simple mix that should give good results.
I dont have any product lines that were 2 parts. I do however have a few 3 part product lines and found with a few additives and some creative thinking you can get pretty close to any profile you would like. Very low P <50ppm gets to be quite a challenge though.
I tell you one thing that really helped me open up the door to a much better variety of profiles was Earth Juice micro blast. The trouble I always ran into was trying to get the Ca up(which is in the "micro" portion of all the 3part lines). EJ micro blast has all the micros and nothing else. Having this in the mix allowed me to find many ways to keep the P down, get the K elevated while not having too much N(which was what I kept running into using a 3part 'micro' for the main source of calcium).

I think with the calculator and a little creativity I will be able to use up all this old stuff while have control over my feed and get some good results to boot. It is a bit ridiculous at times, in the 8 week feed chart I posted up the other day, one of the weeks has 8 products in it and while the last week is nothing but cal/mag and silica blast...lol
If you have any questions about using off the shelf stuff to get a certain profile feel free to ask as I have run a ridiculous amount of product combos through the calc in the last several weeks as well. I would be more than happy to share.


Spurr,
What spread sheet is that that you used for your calculations? Is it your own creation or can it be found on the web somewhere. Thanks
O

 

[spurr]

https://www.crops.org/publications/aj/abstracts/69/5/AJ0690050832

Responses of Greenhouse-grown Cannabis sativa L. to Nitrogen, Phosphorus, and Potassium1

1. C. B. Coffman and
2. W. A. Gentner

Abstract

Growers of illegal Cannabis sativa L. use various cultural practices to maximize crop production. The objective of this study was to evaluate the morphological and biochemical responses of greenhouse grown C. sativa to soil incorporated N, P, and K as they reflect the geographical origin of Cannabis derivatives. Fertilizers were blended with Ap horizon soil from a Gilpin silt loam before placement in 12-cm pots. NH4NO3-N was applied at 0, 25, and 125 ppm. Phosphorus and K from super-phosphate and KCI, respectively, were applied at 0, 50, and 150 ppm. Forty-five-day-old anthesic Cannabis plants were harvested and combined leaf and flower tissues were analyzed for cannabidiol (CBD) and Δg-tetrahydrocanna-binol (Δ9THC). Nine essential elements were also measured in plant tissue. Plant growth, tissue yield, and concentration of CBD and Δ9THC were positively correlated with extractable P2O5 (p < 0.01). Phosphorus concentrations in tissue were similarly related to yield of dry matter and cannabinoid concentrations. 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"*). Growth and tissue yields were negatively related to total plant N (p< 0.01). Levels of extractable P2O5, Mn, B, and Mg were associated with specific concentration ranges for several plant elements plus Δ9THC. Thus, it was possible to partially characterize a soil by tissue analysis. For example, all of the plants grown on soil with less than 100 ppm of extractable P2O5 contained less than 8,000 ppm Δ9THC. Usefulness of such relationships will be dependent upon extensive evaluation of Cannabis on different soils under various cultural conditions. At this time, the reliability required for determination of origin of Canabis derivatives via chemical analysis does not exist when only essential elements and cannabinoids are considered.

I uploaded that paper in full text some months ago (along with other relevant cannabis papers), it can be found here: https://www.icmag.com/ic/showpost.php?p=4191121&postcount=67

Please see this quote from that 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 ...

That study is far from conclusive, and it's pretty darn flawed too. I pointed out a few issues with methodology of that study in another thread here and here (elsewhere too). That said, that study is better than nothing and does provide some evidence that 'high' P levels may increase THCA (and CBDA) ... but no mention is made of trichomes.

 

[spurr]

They were all clones. It was not the exact same line up both grows but there was considerable overlap. In that room we run nothing but clones of proven cuts. We have a small room for seed runs, selection, etc.

Plants grown at 90 ppm P in both grows...clones from the same stock plants...were noticeably more triched out.

From a purely statistical point of view maybe I cannot say with high confidence anything about the yield...but based on my experience with all of the plants involved I do not think there is any difference in yield.

edit...nice looking plants analog. They should be so tasty.

That answers that question. P is important in trich production and there has been anecdotal evidence of this for many years and it has been demonstrated time and again by very good and very experienced growers so I expect you have just demonstrated the same thing. The fact is YS, you also had a Ca deficiency in your latest grow and perhaps Mg as you say. It would have been interesting to see what the yield outcomes would have been without this deficiency.

I'm sorry, but I don't agree "[t]hat answers that question". Granted, what YS wrote is evidence that higher P may influence trichome production, but it's far from conclusive. While I am glad YS is able to add to the dialog in terms of P, he did not prove anything in terms of P and trichomes. There are far too many variables that affect trichome production, which YS was unable to account for, thus, we cannot draw any definitive conclusions from what YS has been nice enough to post for us.

See my post above this one, to SS, wherein I posted a study relative to this discussion about P and cannabis.

The main reason I have doubts that high P will, without a doubt, increase trichome production is that trichome production is not based upon P levels, to my understanding. Trichome production is based upon jasmonates (re MeJA), which are critical to formation of trichomes, as well as other chemicals, but MeJA is the most critical AFAIK. Without MeJA ("methyl jasmonates") trichome production will not be possible, or at least will be very heavily limited.

Not only that, but development of trichomes (ex., glandular and non-glandular) by cannabis (and most(all?) other plants) employ Si (as "silica dioxide"(?), re "silicfied") and Ca (cystoliths) [1,2,3,4,5]. Thus, I am lead to think addition of Si will do more for trichome production than increasing P ... and we know (as I and others have shown) that MeJA greatly affects trichome production. Exogenous application of MeJA or MDHJ ("methyl dihydrojasmonate") will greatly increase trichome production, as well as production of some terpenoids (smell of buds).

Due to the role of Si and Ca in trichrome formation, some academics have suggested an Si:Ca ratio should be considered when fertilizing.

I have done much research into Si, and it turns out many plants (species) can have high Si in plant tissue, even higher than N, if Si is provided in sufficient quantity. IMO, Si should be considered a macronutrient. The application of Si in many studies, found to have high degree of efficacy, ranges from about 1 mM to greater than 5 mM. In terms of cannabis growers, when one would apply Si often, I think the range of 1-3 mM Si is a good goal. And 1 mM Si is about 28 ppm ...

[1] Dayanandan, P., and Kaufman, P. (1967). Trichomes of Cannabis sativa L. (Cannabaceae). American Journal of Botany, vol. 63, pp. 578 - 591

[2] Turner, J.C., Hemphill, J.K., and Mahlberg, P.G. (1980). Trichomes and Cannabinoid Content of Developing Leaves and Bracts of Cannabis sativa L. (Cannabaceae). American Journal of Botany. Vol. 67, No. 10, pp. 1397-1406

[3] Samuels, L., Glass., D.M., Ehret, L., Menzies, G. (1993). The Effects of Silicon Supplementation on Cucumber Fruit: Changes in Surface Characteristics. Ann. Bot., vol. 2, no. 5, pp. 433-440

[4] Botany 404 (2004). XII. Trichomes and secretory structures. Iowa State University, Department of Ecology, Evolution, and Organismal Biology

[5] Han-Yi Fu, H.Y., Chen, S.J., Kuo-Huang, L.L. (2003). Comparative Study on the Stinging Trichomes and Some Related Epidermal Structures in the Leaves of Dendrocnide meyeniana, Girardinia diversifolia, and Urtica thunbergiana. Taiwania, vol. 48, no. 4, pp. 213-223​

 

[spurr]

Spurr,
What spread sheet is that that you used for your calculations? Is it your own creation or can it be found on the web somewhere. Thanks
O

I made it myself.

 

[spurr]

One question Spurr (perhaps I missed it) what media are you growing in?

This round I am using SunShine Mix #4, but normally I use my customized soilless media (i.e., I grow hydroponically because anything non-soil is hydro).

I also use high quality fulvic acid, humic acid, kelp extract (cool processed) and vermicompost/vermicast extract every other fertigation (filtered through 20 then 10 micron nylon filter bags) ... as well as fish hydrosolate every so often. Along with foliar spraying the plants, too.

 

[Storm Shadow]

http://digital.library.okstate.edu/etd/umi-okstate-1509.pdf

Insane information on Si​

​

​

​

​

​

 

[spurr]

I will say this for SS. If you have ever grown Larry OG x anything you will know those are excellent looking buds. That stuff just flat does not grow what anyone would call trophy colas. So I am giving you a big ol well done SS. There is no question that Spurr formula is a good one...the only question is if it is the best one or not.

Agreed. And I am pretty positive there is no "best one" (fert formula) because the plant is a critical partner in what it absorbs considering the plant can self-regulate (to a degree) uptake of P and other elements. That said, I think my mix or slight irritations thereof (ex., higher P in later flowering, higher Si, etc.), may be the cream of the crop in terms of 'off the self' formulas.

What I found...I think...is that P just flat does not influence yield much at all. My plan is to stick to 40 ppm through stretch. But here is where I disagree SS. I think bumping it after stretch, at least for a couple of weeks, increased trichome production quite a bit.

This is something I plan to study in the future, re trichome density relative to P level in fertigation water and leaf tissue assays.

That is based on actually trying it, not on a study.

Same here, I have tested low and high P, many times, and I haven't noticed a difference in trichome production. However, I have not counted trichomes over mm^2 to see if there is a difference in density , or not.

I would love to read about the outcome if you are able to better control variables in your grow and then quantify trichome density of low and high P plants (the former being the control, say 40 ppm), if you can use larger populations (> 5-10) of clones for the control and high P groups. You may have stumbled onto something very worthwhile, but I would like to see more info on the topic.

I also found that while a K:Ca:Mg ratio of 4:2:1 works pretty damn good it does end up showing some Ca and/or Mg deficiencies late in the cycle. This time around I am going to hold most other things equal but go to a 3:2:1 ratio for those things. We will see what we see.

Ditto. When I used a formula with K, Ca and Mg relative quantities of ~4|2|1 (that isn't a ratio ) my plants seemed to lack Ca, more so than with ~3|2|1. I am currently using close to the latter. However, uptake of Ca, as we know, greatly depends upon Vapor Pressure Deficit and root structure (considering Ca is taken up only at root tips, unlike many other elements, which is why I practice root pruning via dry air).

My thinking is that the healthier you keep the plant all of the way to the end the more you let it express its genetic potential. I failed that this time with the Ca/Mg problem. Live and learn.

^^^ yea that, spot on.

 

[spurr]

How much sulfer would be too much? using cns-17, sweet, and big bud. You could get really close to those numbers but the sulfer is at 125

You do not want that much S, and the NO3:S ratio, as well as P:S ratio, is important to consider. I would not use more than ~60-80 ppm S, but that's just my 2cents.

 

[spurr]

@ all,

I am slowly making my way through a backlog of threads, posts and PMs I need to respond to that have built up over the past two moths of my hiatus from ICmag. At this time I am only on page 18 of this thread. However, I noticed a few times people have asked me questions on page 26 and 27, so I 'skipped ahead' to post today.

Over the next few days I will catch up on PMs, posts and threads, including this one.

 

[spurr]

http://digital.library.okstate.edu/etd/umi-okstate-1509.pdf

Insane information on Si​

Going to read that soon, thanks.

P.S. Could you not have used smaller font?!

 

[spurr]

Spurr we hardly agree on anything but I still enjoy your input. It's a very valuable part of the metanarrative happening here.

Ditto. We may have been at each others throats (re Phi vs Pi), but I hope we can let bygones be bygones for the betterment of our community ... which seems to be the case

Re Si, there are some that are now saying it should be listed as an essential mineral element. Others also say that Ni should be listed as an essential mineral element.

Yup, both Si and Ni should be considered essential, maybe though with a looser definition of "essential" than is traditionally used (re a plant cannot live/grow without element X).

As for debating on P that's why we're here and I am completely open to findings. Dogma is the mother of all ignorance. Let's see where this all goes is my only thoughts - however there seems to be benefits exhibited by cannabis where higher P is present.

I too would like to 'see where this goes'. At the very least, I am of the strong opinion 'high' P (ex., > 60 ppm) during veg and pre-flowering is not a good idea.

 

[Storm Shadow]

This thread seems to be back on track! Nice

The anomaly of silicon in plant biology

http://www.pnas.org/content/91/1/11.full.pdf


Silicon Transport

http://docs.google.com/viewer?a=v&q=cache:qKi06J-DzWMJ:www.osti.gov/bridge/servlets/purl/761913-WGWYBX/native/761913.pdf+si+uptake+trichomes&hl=en&gl=us&pid=bl&srcid=ADGEESite9kUH0ic9TMfpSiB_8ZZbIHcqtBNomfOGCJ4YBZyQGnpehWbm9puOzUzVqesPowRmWMnmdO5mDtlaj4MtU8x9kbniBPoEzajnGaH23zaQmDbREuDsTmkGkZhP3OvsGPxhUQC&sig=AHIEtbR4lZgJE-HHxSSqvxqJkm-FJ3Sz8A