The myth, of the high P myth?

[spurr]

When growing in soil high doses of P kill the fungi in the soil or make it go dormant. These fungi are the very same microbes which supply the bulk of P to the plant. Never use ferts over 10 -10 -10 in soil or else you kill off your microherd.

Yes, once P exceeds ~20 ppm the most commonly used species of AM fungi (ex. G.mosseae) are hindered, and once it exceeds ~30 ppm those same species stop sporulation, infection and are greatly hindered [1].

You can use 10-10-10, but what matters is how much of the 10-10-10 is used in terms for AM fungi, equating to ppm of P. FWIW, high ppm will not kill the microherd as a rule, it's not black and white. I have been running some tests making ACT with water that has various levels of General Hydroponics fertilizer (< 600 ppm total; see link in my signature). Once I buy MicrobeMan's Microbobulator this week, or next, I will start testing in earnest with pictures and video from my microscope doing DME assay, etc. I am prodding CTGuy to also test the affects of chem fertilizers on making ACT; as well as testing microherd in media after drenching with chem fertilizers, etc. IIRC, Dr. Ingham as written up to 600 ppm is OK with compost tea, but I am not sure she did write that, and not all elements affect biota the same...

[1] "On-farm Production and Utilization of AM Fungus Inoculum"
David D. Douds, Jr., Ph.D
USDA-ARS Eastern Regional Research Center
http://www.extension.org/article/18627

To aid the conventional grower in this decision, we conducted an experiment to describe the response of AM fungus colonization of tomato and pepper roots to added P. Plants received, three times per week, 10 mL of a balanced, complete nutrient solution (Hoagland and Arnon, 1938) adjusted to supply P levels ranging from 0.31 to 62 ppm P as KH2PO4. Nitrogen was supplied as KNO3 and Ca(NO3)2 and was 210 ppm for all treatments. Results underscored the need to control P applications and showed that colonization decreased with increasing P level to effectively zero at 32 ppm P (Fig. 4).

 

[FlaDankster]

I fucin love you guys!

Mullray you got it right bro.......a thread on humic and fulvic is a good idea.And it would be great to see yas and spurr and YS guiding it along.Despite any difference in opinions between you and spurr the two of ya make for a good read....minus da bullybullchit.

Between three(mainly)of you guys this thread is turnin out to be really fookin good guys.

More pics please YS!

 

[Carboy]

Conventional Wisdom

Conventional Wisdom

I've always heard fulvic for hydro; humic for the rest.
Of course, I've been bit in the ass before by going on what 'they said' before.
Sourced fulvic from Super-Grow in the past, but that is a dead horse. Getting a material analyzed is out of my realm but it seems a guarantee of product would be the first place to start. My method of "Oh, a teaspoon per 5 gallon looks right." could no doubt be improved too!
CB

 

[spurr]

I fucin love you guys!

Mullray you got it right bro.......a thread on humic and fulvic is a good idea.And it would be great to see yas and spurr and YS guiding it along.Despite any difference in opinions between you and spurr the two of ya make for a good read....minus da bullybullchit.

Between three(mainly)of you guys this thread is turnin out to be really fookin good guys.

More pics please YS!

Hey there FD,

I will not be part of any thread by Mullray. He does not properly reference his claims and makes too many assumptions and is just flat wrong too many times. For the rest of my response to your post, check your PMs. Fwiw, Mullray is wrong about his 'take' on that article he posted, far too many assumptions...




Now back to phosphorus...

 

[YosemiteSam]

Nicely, nicely. I will subtract what I am supplying through the roots and then supply the rest by foliar. That info at least gives me a starting place where I know I won't fuck up an entire grow.

Is it true that through the roots boric acid is the most effective way to supply B?

edit...btw, someone gave me a small sample of Bio-90 (http://www.kalo.com/products/Detail.aspx?ID=fd636365-5a33-41a3-9d6a-ff3a32f66dfd&Type=2). Holy shit, what a difference it makes. I may just have to rethink my opinion on NIS...clearly better than yucca plant extract...in another league honestly.

Sat will be 7 weeks into flower. I will get some pics that night and post them Sun or Mon. As near as I can tell low P has not cut down on resin production one bit.

YS, I used to supply a local hydro shop with a mix that when diluted in solution gave 2.8ppm boron in solution. Their customers raved about it and most were growing mj. I don't think anyone is likely to know optimum for cannabis but my advice is keep lower rather than higher. Boron toxicity is difficult to correct.

 

[YosemiteSam]

I ordered the gem scale (thanks for the link) so I can try new and fun ways to screw up my plants. But yea I could see making your own solution like that...just use enough distilled water that 0.1 gram is accurate enough.

The NIS I used is just what this guy had. I have no opinion on if it is a good, or the best NIS...no experience. Still I was simply amazed by what I saw....no beading at all other than what runs off when you spray too much...otherwise it just went on nice and flat and when it dried (pretty quickly, much more so than with yucca) it left no film at all. Totally impressed.

And I see your point about just adding some boric acid to the nute mix. Anything that moves through the phloem probably has no advantage at all to being sprayed unless you are in dirt and tissue analysis (it sucks that there is no reliable database for weed numbers) says you need more.

I still think elements that count on transpiration to move can benefit from foliar sprays...but just a theory I happen to believe...no proof from me that should convince anyone else.

 

[spurr]

Nicely, nicely. I will subtract what I am supplying through the roots and then supply the rest by foliar. That info at least gives me a starting place where I know I won't fuck up an entire grow.

Is it true that through the roots boric acid is the most effective way to supply B?

Do you mean supplying B via roots vs leaves? If so, then the answer is yes and no: it depends upon the species. Did you read the references I posted? The first one is relevant to your question. Boron, like Ca, is 'sucked' into roots with water due to transpiration from leaves. However, B moves poorly within phloem of many species...

A source of B many soil farmers use is borax (salt of boric acid, sodium hydroxide and sodium carbonate), but boric acid or sol-u-bur are better sources for fertilizer mixes. Using sol-u-bur is the best choice IMO because it's completely water soluble and high concentration (IIRC ~20% B). You can get sol-u-bur from J.S.Peters and get boric acid from Hydro-Gardens. I would suggest sol-u-bur, FWIW.

edit...btw, someone gave me a small sample of Bio-90 (http://www.kalo.com/products/Detail.aspx?ID=fd636365-5a33-41a3-9d6a-ff3a32f66dfd&Type=2). Holy shit, what a difference it makes. I may just have to rethink my opinion on NIS...clearly better than yucca plant extract...in another league honestly.

Yup, a good NIS is far better than yucca, I wasn't pulling your leg Also, see what I wrote about probably the most ideal NIS for ionic spays: alkyl polyglycoside. It has been found to reduce half-time penetration of ions like Ca from 204 hours to 17 hours!

For very high effectiveness from a surfactant the surface tension of water should be ~25-30 dyne/cm. Using AGNIQUE PG 8105 at 0.1% (i.e., ~1,000 ppm) in deionized water at 25'C will provide 28 dyne/cm. Using AGNIQUE PG 8105 at 0.01% (i.e., 100 ppm) gives 34.8 dyne/cm in deionized water at 25'C (78'F).

I linked to a company selling alkyl polyglycoside surfactant derived from coconut and corn in a previous post, i.e., "Congnix" brand. I plan to try and source Cognix AGNIQUE PG 8105 to test instead of using Douse. If you are going to buy a NIS, I would suggest trying what I plan on trying...especially if you are concerned about the chemicals used in good NISs.

Here is a quote from the Cognix brochure (link to PDF) about their alkyl polyglycoisde surfactant "AGNIQUE". Here (link) is the website for their NIS.

Cognix AGNIQUE PG alkyl polyglycoside surfactants are readily biodegradable and exceptionally mild. However, unlike conventional nonionic surfactants, the manufacturing of Cognis' surfactants is based entirely on renewable raw materials [i.e., coconuts and corn].

The ingredients in "Bio-90" are: 90% Alkylphenol Ethoxylate, Propylene Glycol and Tall Oil Fatty Acids.

The ingredients in "Douse" are: Ethoxylated Alcohol, Glycol and Dimethylpolysiloxan
​

Oh yea, I made a typo when I was writing to you about various types of foliar surfactants and adjutants. I wrote CCO as "Concentrated Crop Oil", but I meant to write COC as "Crop Oil Concentrate". I will fix that later in the older posts.

Lastly, do not use > 1 ppm B for your growing style in coco; over 2 ppm B is way too high. Plants that do well with high B, such as alfalfa and sunflower, don't even need > 2 ppm B. I have found not found any scientific and botanical evidence that we should use > 1 ppm B, let alone > 2 ppm B. It's best to stick with well proven levels of B, e.g., 0.25-0.5 ppm for soilless and hydro; I am going to use 0.3 ppm in fertigation water for soilless. I do not believe the claim made by mullray you quoted, re: that he provided 2.8 ppm B...and you should not either, or at least do not try to use > 2 ppm B; keep it =< 1 ppm.

See this excerpt from "The Fertilizer Encyclopedia", by Vasant Gowariker, V. N. Krishnamurthy, Sudha Gowariker, Manik Dhanorkar, Kalyani Paranjape, Norman Borlaug (2009):

The soil pH influences the availability of boron; the higher the pH, the lower the boron uptake and the greater the deficiency. Generally, for the same type of crop, the application rate of a fertilizer containing water-soluble boron is lessor for coarse soil than for fine-textured sand soils. Apple, alfalfa, asparagus, beet, celery, sunflower are some of the crops requiring high levels of boron (more than 0.5 ppm), whereas carrots, cotton, lettuce, peanuts, peach, sweet potato, tobacco and tomato need only 0.10-0.15 ppm boron. The requirement of barely, beans, citrus, corn, forage grasses, soybeans and strawberry is lower than 0.1 ppm of the available soil boron.

Interaction of boron with nutrients plays a critical role in the efficiency of the use of boron. For instance, boron is particularly effective with phosphorus, potassium and micronutrients, whereas its efficiency suffers with sodium, calcium and magnesium. For a good crop, it is essential to have a correct calcium to boron ratio.

In an article by Donald Lester in Maxim Yield, titled "Chelated Micronutrients" (link), he claimed B can not be fully chealted, only complexed. I am unsure if that claim is correct because he did not reference his source, like is the case so with many people (sadly, the need to reference claims is lost on most people).

 

[spurr]

The NIS I used is just what this guy had. I have no opinion on if it is a good, or the best NIS...no experience. Still I was simply amazed by what I saw....no beading at all other than what runs off when you spray too much...otherwise it just went on nice and flat and when it dried (pretty quickly, much more so than with yucca) it left no film at all. Totally impressed.

See what I wrote above about the best type of NIS and surface tension of water, etc. If the water is drying quickly add humic acid, becuase *you do not want* the leaf to dry quickly if your RH is below the POD of the salt (ions) you are applying.

And I see your point about just adding some boric acid to the nute mix. Anything that moves through the phloem probably has no advantage at all to being sprayed unless you are in dirt and tissue analysis (it sucks that there is no reliable database for weed numbers) says you need more.

I still think elements that count on transpiration to move can benefit from foliar sprays...but just a theory I happen to believe...no proof from me that should convince anyone else.

As I wrote, boron, just like Ca, does depend upon transpiration to move into roots. Also, B in some species moves poorly in phloem, see the many boron references I posted.

Please, stop believing what mullray writes just because he writes it...critically analyze what *everyone* writes and *ask for references*.

 

[YosemiteSam]

Albion sells Boron as an amino acid complex...not a chelate. Their explanation to me is that for something to be chelated the ligand (generic term for the molecules being attached) must be able to attach in two places to form a ring structure. With Boron the ligand can only attach in one spot...a complex rather than a chelate. The same is true for K.

That is straight up chemistry...no citation is needed, take a look at the actual chemistry and all will be revealed.

Literature on B is all over the map with the one thing in common that it is plant species specific. We sure as fuck do not know what the optimum level in marijuana is cause there are not exactly a plethora of studies. From my reading I am not convinced we know how it moves in plants for sure.

So if I wanna try above 2 ppm (i am currently at .5 ppm) why would anyone care? Why wouldn't someone just think cool...let him take the risk with his grow and let me see how it works? Ultimately I do not want to grow avg plants so playing it safe and not going out of the box just is not on my agenda. BTW...I have the grow the pics are from and I have a friend with a 3 600 watt light grow. We use the small grow for testing (or strain hunting or sativa growing for personal smoke) and then transfer from there to the bigger grow...so it isn't like I am going to lose everything...hell I could go one plant at a time if something really concerns me...3 ppm B ain't on that list.

Anyways...been talking with some peach tree growers and they do not give me a lot of citations...but they can sure as hell tell me how different things they have tried have affected their yield and quality...and sometimes thats all it takes for me to give something a shot. They like foliar B, Zn, Ca and sometimes K...in spite of working very hard to develop soils that deliver proven levels of elements.

As far as a database I am happy to contribute. Far as I am concerned we can just start a thread right here. Whether or not I am willing to give exact yields I will have to think about...but relative %s no problem.

With enough input we should be able to at least come up with some guidelines...maybe somewhat broad ranges at least. Ideally we would want someone with design of experiment cred...and enough contributors to hit some degree of confidence...hell I would be happy with 75% at this point.

Course you are going to always have people that think their strain needs something completely different along with those that think there are secret ingredients in hydro store nutes (or special forms of the salts). Not gonna change those peoples opinions...which is fine with me, everyone is entitled to an opinion.

edit...I will take a look at the Cognix stuff, that sounds good.

 

[spurr]

Albion sells Boron as an amino acid complex...not a chelate. Their explanation to me is that for something to be chelated the ligand (generic term for the molecules being attached) must be able to attach in two places to form a ring structure. With Boron the ligand can only attach in one spot...a complex rather than a chelate. The same is true for K.

That is straight up chemistry...no citation is needed, take a look at the actual chemistry and all will be revealed.

I am well aware of what constitutes an ion chelate and ion complex, my point was that article offered no references showing/explaining the chemistry of boron and chelators. References are always needed and should always be provided when a claim is made that is not common knowledge, e.g., *why* boron can not be truly chelated. But it's good to read what the folks from Albion told you, even though it doesn't explain why.

Literature on B is all over the map with the one thing in common that it is plant species specific. We sure as fuck do not know what the optimum level in marijuana is cause there are not exactly a plethora of studies. From my reading I am not convinced we know how it moves in plants for sure.

No not really, lit of B is pretty straight across the board, e.g., 0.1-1 ppm is the range for most species; and a 'safe' application rate for species that are not defined as B sensitive, when their sufficient range of B is unknown, is ~0.25-0.5 ppm. And for B tolerant species ppm range of ~0.5-1.25 is sufficient depending upon media or hydro, pH, rate of transpiration from leaves, etc.

So if I wanna try above 2 ppm (i am currently at .5 ppm) why would anyone care? Why wouldn't someone just think cool...let him take the risk with his grow and let me see how it works?

I care because the claim made by mullray is beyond the pale considering he provides zero scientific and/or in-field horticultural evidence and proof. If you mess up your plants, fine, but many people reading are not so willing to mess up there plants as you, are for the sake of discovery. If many people reading hinder there plants they are not happy at all. What I wrote was not only to you, re: the level of B we should stay under; it was to anyone reading that may want to try using B.

That said, I would be interested in reading your anecdotal evidence from supplying B higher than 0.5 ppm in coco.

 

[YosemiteSam]

First I would normally be in a position where I could do that trial. The room where I would do it is 5 weeks into flower with 7 plants that will finish at 9 weeks or there about and 3 that are going to go 14 weeks. My next planned run is going to be a seed run looking for personal smoke...so lots of sativaish stuff that is going to take a while (TH Haze, TH f2 Haze, TH f2 Deep Chunk x Haze, f2 Cherry Malawi and Deep Chunk x Cherry Malawi).

I might could add 4 or 5 pots though of something I am familiar with running for the trial. Take clones off the same plant to minimize that variable...guess I better get on that.

I am guessing I could just take my normal hydro special/CaNO3 formula which has .5 ppm, dump that into some 5 gal buckets then add solubar to achieve the levels we are wanting to look at.

Still from the statistical side that sample size would mean the results may not be reliable or repeatable. Plus I do not have a plant that I have kept enough records on to even determine the avg yield of or the standard deviation. But I guess we need to start somewhere.

I am curious about your PK formula. Would you just add that on top of the normal formula at certain times? I have everything on hand except folic acid.

Edit...I do agree no one should be upping B except as an experiment at this point. I merely want to find out if there are actual benefits to running higher than normal B and where the line is that it becomes toxic.

 

[tester]

20g/L potassium nitrate
110g/L MKP
110g/L magnesium nitrate
1.5g/L abscorbic acid
0.2g/L folic acid

@ 1 liter concentrate (numbers are in mg/l as usual)

• 15000 NO3
• 25000 P
• 40000 K
• 10000 Mg
• 1500 Ascorbic acid (Vitamin C)
• 200 Folic acid (Vitamin B9)

The concentrate @ 2.5ml/l

• 37.5 NO3
• 62.5 P
• 100 K
• 25 Mg
• 3.75 Ascorbic acid (Vitamin C)
• 0.5 Folic acid (Vitamin B9)

 

[BasementBreeder]

On the actual topic of phosphorus levels in solution,

In Hydroponics: A Practical Guide for the Soilless Grower by J. Benton Jones Jr. it says 30-50 ppm is the standard amount in nutrient solutions. However, the author personally recommends 10-20 ppm.

Thoughts on this?

 

[spurr]

@ BasementBreeder:

On the actual topic of phosphorus levels in solution,

In Hydroponics: A Practical Guide for the Soilless Grower by J. Benton Jones Jr. it says 30-50 ppm is the standard amount in nutrient solutions. However, the author personally recommends 10-20 ppm.

Thoughts on this?

I for one plan on testing a low P mix (10 ppm) for use with biological organic growing with AM fungi (and compost teas) in soilless media. I will quantify (or send out for testing) the infection rate of AM fungi (via root staining assay) and rate of sporuation of AM fungi (spore counts) and approximate size of mycosphere; all as a means to see the health/growth of the AM fungi (G. mosseae). I won't be testing the 10 ppm P for a little while though, I need to culture some G.mosseae first (for inoculation of cannabis roots) and that takes at least month using Bahia grass.

The level of P needed depends on a few factors, such as growth rate, media temperature and type (ex., AEC level), as well as non-chelate Ca, Mg and micronutrients (such as Fe, Al, etc.) that can bind to P. Also a factor is the watering style, P has poor mobility in the soil solution (aka soilless solution), thus if using drip emitters I would use higher P than if using drench method or hydro.

Also worth noting is a study I uploaded that found P was positivity correlated to THC and CBD level, more so THC, to a substantial degree. While it was only one study, and there are others that seem to contradict those findings, it is worth considering. I use low P in veg and flowering (~40 ppm), but I plan to test higher P in later flowering (~100 ppm) vs lower P (~40 ppm) and compare THC and CBD levels in bud (as well as Brix level, rate of photosynthesis, etc). This testing will take at least six months to complete, I need to first buy a Chl fluorometer for quantifying rate of photosynthesis.

For this coming grow (starting at the end of this month) I think I may send out weekly or bi-weekly petioles to be tested for all macro and nearly all micro elements, as well as weekly or bi-weekly soilless samples to be tested for plant available nutrients. I also have a nice refractometer I will use to test dissolved solids in plant sap (> 12 Brix is good), and I am getting a plant sap pH pen to test pH of sap (ideal pH of sap is 6.2-6.4; above or below can indicate deficient nutrients*). Using those tests I should be able to gather useful data on cannabis P needs, as well as other elements. Albeit the data set won't be huge, so I will continue with petiole and media testing for a few grows with various cultivars and races to increase the data set.

* "A balanced level of nutrients in the leaf of the plant will show an ideal pH level of 6.2-6.4. A lower than ideal pH level will indicate a deficiency in the following minerals: Calcium, Potassium, Sodium or Magnesium. A higher than ideal pH level will indicate a deficiency in the following minerals that act in the opposite direction: Phosphates, Nitrate Nitrogen, Sulfates and trace minerals." (link)​

Hope you find that info useful

 

[YosemiteSam]

I like the sound of that test spurr. Have you located a lab for the tissue testing...I cannot find one that wants to be involved in such a thing.

I have a refractometer myself. 12 is a number on the high side for me, when I get close to that my plants are doing fine. However, my partner and I cannot split a sample and get the same reading to save our life. Relatively it appears to provide some info but for absolute accuracy it is not so good.

Anyways, good luck with the test.

 

[spurr]

I like the sound of that test spurr. Have you located a lab for the tissue testing...I cannot find one that wants to be involved in such a thing.

I am not going to tell them what they are testing, if they ask I will tell them a plant with very similar petiole morphology as cananbis. I plan to wash the petioles in distilled water with a toothbrush, then use my food dehydrator at 95'F for 24+ hours to fully dehydrate the sample before sending. They want > 20 petioles per test, but that's a lot for my sized grow at this time, so I may send smaller numbers, 5-10 per test if done weekly or 20 if done biweekly. I may test biweekly for now because each test is ~$70 USD.

I hope by washing the petioles in distilled water with a toothbrush and dehydrating them I will remove any tell-tall smells, and I won't send any petioles with trichomes on them. I will use an anonymous pre-paid credit card with an anonymous email address and my safe-addy I setup with a fake drivers license.

I will buy Cardy nitrate and potassium meters soon, but even with those, you only get nitrate and potassium. I am buying the Cardy ph pen for testing pH of sap; and I may buy the Cardy EC pen for plant sap. Albeit I will not get the EC pen for a while, each pen is about $250 USD.

I have a buddy, ncga, that has been using the Cardy meters on his outdoor grows for many years. He has a lot of data collected, as well as with a refractometer. I plan to hit him up for suggestions and info on the data he has collected over the years.

I have a refractometer myself. 12 is a number on the high side for me, when I get close to that my plants are doing fine. However, my partner and I cannot split a sample and get the same reading to save our life. Relatively it appears to provide some info but for absolute accuracy it is not so good.

What type of refractometer? Is it auto-temp compensating? I may buy a digital model to compare to my non-digital model, both with auto-temp compensation. When you and your partner "split" a sample, that means you both use sap from the same extract, yes?

One thing about Brix is it's affected to a large degree by sampling method (time of day, days past fertilization, etc), temperature, N and K levels, as well as irradiance, etc. I think trying to account for N and K when taking Brix readings will make them a bit more accurate.

That said, I do agree that a refractometer is only a piece of the pie, and not good for absolute accuracy. FWIW, a buddy of mine gets constantly higher readings after applying aerated compost tea to his conventional fertilizer grows (foliar and media application).

Anyways, good luck with the test.

Thanks. I forgot to mention I will get my fertilizer mix tested (even though I am making it myself with the Nutron2000+ software) as well as my water (from a very good RO unit).

 

[YosemiteSam]

This is the one I use http://www.groworganic.com/catalogsearch/result/?q=refractometer&x=33&y=8

I think it is good for me comparing my own plants but not so good for you and I comparing numbers. That is, when we abuse a plant it is clear from the readings that they don't like it, conversely after Ca sprays brix always goes up some.

Little wheat grass juicers are good for getting sap samples btw.

Sounds like you are stocking up on lots of fun toys. I would love to get my hands on a Cardy nitrate sap meter.

 

[PointofNoReturn]

Sorry for beeing totally offtopic. But maybe one of you can give me a legit Answer to my Question. Does low % RH in earlier Stage of flowering hinder growth of calyx? y/n is plenty enough^^

Im a little fed up with Reading Comprehension of some, so i thought i would try, without bothering you with PM.

Thx, keep up the good work.

 

[spurr]

Sorry for beeing totally offtopic. But maybe one of you can give me a legit Answer to my Question. Does low % RH in earlier Stage of flowering hinder growth of calyx? y/n is plenty enough^^

Im a little fed up with Reading Comprehension of some, so i thought i would try, without bothering you with PM.

Thx, keep up the good work.

Who are you asking? I don't recall you asking about RH in this thread, but I might have missed it. I for one do not know if low RH hinders calyx development. However, looking at RH alone isn't sufficient, also taking canopy temp and average leaf temp into account is a good idea. And like you noted, this is way off topic to this thread

 

[PointofNoReturn]

Sorry for the Confusing, you didnt missed any Question before. One of you = the 3-4 people keeping this thread alive with insight knowledge on plants, figured i might get a quality Answer. Posting a new thread maybe futile, my english seems to be kinda bad,when usually noone gets my question.