Cannabis tissue nutrient analysis

Grower Z

New Member
This file (is there a way to attach files to a post?) is from the website of the International Fertilizer Industry Association.

It is a summary of data from three older studies...

an excerpt:

11j3m09.jpg

Note: Plants were grown in "chernozem", which is a Russian word meaning "black soil" and is a humus rich and very fertile loamy (nutrient rich) soil found all over the word in various places typically of cool to temperate semiarid regions (ex., grasslands), it is very good soil for growing plants.

Typical nutrient profile of chernozem (Melent’ev, et al, 1999)

* Total Nitrogen = 0.61%
* P2O5 = 0.15%
* Ca = 0.049%
* Mg = 0.012%
* CEC = 15 – < 40 meq/100 g
 
I'd be shocked if Biksa isn't talking about cannabis, without writing the word cannabis in this one: I suppose he could be talking orchids or something else, but...


Nutrient Ratios for Modern Crops
by Erik Biksa 2009-08-01

To answer the first part of the question, as indoor growers we are applying too much phosphorous because the recommendations for applications and formulations have been based on outdoor field agriculture practices, which simply don't apply directly to indoor gardens. In nature the soil is very deep, and roots do not occupy the entire body of soil as they do in containers, beds or systems found with indoor gardens. Phosphorous leeches from the root zone in natural soils quickly, washing away from the contact zone with plant roots, as it drains with water further into the depths of the earth. To ensure a healthy supply of phosphorous, outdoor conventional field agricultural growers do a sort of "over-application" of phosphorous, because it has been determined that much of it will be quickly leeched away from the plant roots; what remains at any given time can be taken up by the crop. From this, we can learn that excessive "P" values in our N-P-Ks are not necessary for indoor growers, where phosphorous maintains a high level of contact within the root zone of plants grown in artificial soils and in containers, beds and systems commonly found with intensive indoor growing environments.​


Three part base nutrient systems have been widely used and accepted through the indoor gardening community, and have been delivering great results for years. Based on modern research conducted on indoor grown high yielding crops, it was determined that using the three part nutrient system actually produced better results when being applied in a 1:blushsmile:1 ratio versus the common 3:winkyface:1 ratio, especially when bloom boosters intended for indoor crops were used in conjunction with the three part nutrient system. 2:1 ratios of three part base nutrients were the least effective of all (where the "grow" component was omitted entirely through the bloom phase).

Upon analyzing the nutrient levels and ratios achieved in the nutrient solution for feeding indoor crops in the bloom phase, applying the base nutrients in a 1:blushsmile:1 ratio using popular three part nutrient components, the level and ratios much more closely resembled those of the internal nutrient levels and ratios of the plant being grown versus using the three part nutrient components in the common 3:winkyface:1 method.​
 
What's more amazing is how many think this is crap. There is a lot of "the blind leading the blind" in out industry and communities.

Like you, I try to bring the information to their attention, but too often it falls on deaf ears, or as I like to say, "It goes in one ear, and picks up speed heading out the other".


You might want to see if the Mods can move this to an appropriate forum. Somehow it is stuck at the bottom of the home page. I found it by accident.
 
I'm amazed at how little P is actually used in the plant, this may have just changed my soil mix.
 
I'm amazed at how little P is actually used in the plant, this may have just changed my soil mix.

Yep the entire problem with the amount of p used if growing in a contained growing space i.e a pots,ebb and flow buckets,dwc etc the phosphorus is unable to be washed away deeper into the medium out of reach of the roots, I also was pretty good in science in high school and if I remember correctly phosphorus is also highly water soluble as well making it even easier to wash away.

So now that I have moved indoors I am wondering if anyone uses GH 3 Part in soil what kind of ratio do you use I have so far had suggestions of before planting to nutriate the soil with 5ml grow 10ml micro 5 ml bloom before planting as I use promix bx and 40% perlite and then from that point on feed at a ration of 40% of what the label reccomends but not sure if that is the best way to go.
 
Hey guys,

I have recently come across this study as well, and was quite shocked, but not suprised?! I am an LED grower (now), who is just slowly dialing in my program, through my second LED grow. They are on an organic schedule, and can really eat! I have not been able to max them out yet with my nute schedule (no burn). My current grow, which is bigger than the last (plant size wise), has started to show signs of nitrogen loss higher up. They are half way through flower, and have started to pull N from the upper fan leaves that are getting 100% unobstructed light throughout the 12 hour day. As with most programs, mine has a slight dip in N, but has low P, and high K. I have just modified my schedule, and added more N. We shall see how that works!

I do plan to start a journal in a month or so, and have an agressive, and super agressive program, upping the N for veg and flower, to prove or bust this myth!

Example: veg=15/2/18-flower=18/8/22 versus veg=10/2/12-flower=8/6/15
 
Hey guys,

I have recently come across this study as well, and was quite shocked, but not suprised?! I am an LED grower (now), who is just slowly dialing in my program, through my second LED grow. They are on an organic schedule, and can really eat! I have not been able to max them out yet with my nute schedule (no burn). My current grow, which is bigger than the last (plant size wise), has started to show signs of nitrogen loss higher up. They are half way through flower, and have started to pull N from the upper fan leaves that are getting 100% unobstructed light throughout the 12 hour day. As with most programs, mine has a slight dip in N, but has low P, and high K. I have just modified my schedule, and added more N. We shall see how that works!

I do plan to start a journal in a month or so, and have an agressive, and super agressive program, upping the N for veg and flower, to prove or bust this myth!

Example: veg=15/2/18-flower=18/8/22 versus veg=10/2/12-flower=8/6/15

:reading420magazine: I'll keep an eye out for it :peace:
 
I know this is an old posting /thread but I think it deserves to be bumped.

And besides I have a question that sort of relates to uptake of Nutrient's.

Has or does anyone consider the uvb lights ?
Exposure to ultra-violet B (UVB) rays in order to synthesize vitamin D3 and in turn, metabolize calcium. Is an important issue with MJ.
How would a person monitor this without a soil report?
:peace:


 
The more I think about it the more I see less need for phosphorus application. Of course everything is needes in balance, but cannabis uses a lot of nitrogeb at least till middle veg! Why would it otherwise be pulling it from fan leaves when the time comes? I also agree that overapplication of N can lead to leafy buds and grassy taste, but N & P coexist to help uptake one another. In other words, there won't be stable P uptake without nitrogen in the soil. Blocking its availability partly is in my opinion a way to go, but without artificial lowering of its content.
 
Hello Everyone,

Currently I am researching cannabis plant nutrition and have performed nutrient uptake analysis and tissue analysis. I am only in the initial phases of the tissue analysis but my data on nutrient uptake goes back a few years. One thing i've noticed is that the chemical composition of the leaves changes with the nutrient availability. In other words, if you are running 40ppms of phosphorous in your nutrient solution your leaves may show 0.5% P but if you raise the phosphorous to 60ppms you will see the P go up to about 1%. So far I have seen a relatively wide range in %'s for nutrients in healthy leaves. The numbers that AN supposedly published are in the safe zone but they definitely don't tell you anything useful in a general sense. At the end of the day, as long as your nutrients are available in the correct amounts in your water your roots will take them up in the correct amounts and your plants should be healthy barring any environmental issues or bugs/fungus etc.

VB
 
Hello Everyone,

Currently I am researching cannabis plant nutrition and have performed nutrient uptake analysis and tissue analysis. I am only in the initial phases of the tissue analysis but my data on nutrient uptake goes back a few years. One thing i've noticed is that the chemical composition of the leaves changes with the nutrient availability. In other words, if you are running 40ppms of phosphorous in your nutrient solution your leaves may show 0.5% P but if you raise the phosphorous to 60ppms you will see the P go up to about 1%. So far I have seen a relatively wide range in %'s for nutrients in healthy leaves. The numbers that AN supposedly published are in the safe zone but they definitely don't tell you anything useful in a general sense. At the end of the day, as long as your nutrients are available in the correct amounts in your water your roots will take them up in the correct amounts and your plants should be healthy barring any environmental issues or bugs/fungus etc.

VB

That makes sense. Do you perform gas chromatography? Do all proportions between N, P and K change while P is going up? Did you somehow manage to figure how it influences veg and flowering?
 
Hello Everyone,

Currently I am researching cannabis plant nutrition and have performed nutrient uptake analysis and tissue analysis. I am only in the initial phases of the tissue analysis but my data on nutrient uptake goes back a few years. One thing i've noticed is that the chemical composition of the leaves changes with the nutrient availability. In other words, if you are running 40ppms of phosphorous in your nutrient solution your leaves may show 0.5% P but if you raise the phosphorous to 60ppms you will see the P go up to about 1%. So far I have seen a relatively wide range in %'s for nutrients in healthy leaves. The numbers that AN supposedly published are in the safe zone but they definitely don't tell you anything useful in a general sense. At the end of the day, as long as your nutrients are available in the correct amounts in your water your roots will take them up in the correct amounts and your plants should be healthy barring any environmental issues or bugs/fungus etc.

VB

Hi VB!
Any updates with this? I would love to see your accumulated data and talk database development with you. I'm working on a similar project myself.
Cheers!
KYM
 
Hi VB!
Any updates with this? I would love to see your accumulated data and talk database development with you. I'm working on a similar project myself.
Cheers!
KYM

Hi,

Seems like no one is responding on this thread.

Anyone doing leaf analysis that is more complete? Good vs bad plants?

Regarding the P myth. You all are going the wrong direction. Hi P is critical. P is the only element in the energy molecule ATP! What is in solution in the soil or medium and what is absorbed are two different things. Realize we need 10 times more calcium that potassium in a good soil, yet, in many crops, there is more potassium than calcium in the leaves. Do not think about extractions. That is all wrong.

Hydroponics is another issue. I have no experience in it.
 
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