The myth, of the high P myth?

[spurr]

One point I think has not been discussed in this thread: AM fungi ...

AM fungi (arbuscular mycorrhizal fungi) are greatly hindered by P levels above ~30-35 ppm. And as we all know, it has been found AM fungi offers many benefits to plants. The issue of time to infection of host (re efficacy of AM fungi on plants) and spore germination notwithstanding, using low P, say ~30 ppm along with AM fungi (from veg till harvest), might be something to look into for conventional growers (if they do not let the soilless solution accrue over ~30 ppm P).

 

[spurr]

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

Nice find. I only read the abstract so far, but it looks good. I have a few other papers on par with the topic in that paper. Addition of Si is important for all growing styles, but especially when not using healthy soil ...

Of interest here I believe, is that Si has been found to increase yields of many plant fruits and flowers. And I have noticed better yields with cannabis when using Si vs not using Si, not to mention much stronger plants (cells).

Also, I have read (vague) references in two studies about the supposed ability of Si to act as a SAR (Systemic Acquired Resistance) inducer. However, I do not put much faith in that claim at this time, it's something I only spent a short time researching so far.

 

[Storm Shadow]

http://www.bashanfoundation.org/horst/horstgardensage.pdf

Effect of phosphorus uptake on growth and
secondary metabolites of garden sage

 

[Storm Shadow]

http://www.scipub.org/fulltext/ojbs/ojbs8349-56.pdf

[FONT=TimesNewRoman,Bold]

Induced Resistance in Mycorrhizal Tomato is correlated to Concentration of Jasmonic Acid​

[/FONT]

 

[spurr]

@ mullray,

I believe at on point in this thread you suggested that I (and/or others) may have gotten the 'idea' about the 'high P myth' from 'Big Mike' of AN infamy. IIRC, at one point you suggested the main reason you do not believe in the 'high P myth' is because it came from Big Mike. I just wanted to point out, if you did make that suggestion, I was unaware of Big Mike's claims about P before I looked into the topic, tested low P and wrote about the P issue here, and elsewhere.

 

[spurr]

One quick thought that may have been pointed out already:

I believe the idea of using high P during veg and especially pre-flowering and flowering came from the likes of Mel Frank, et al., many decades ago. And I very highly doubt Mel Frank made use of plant physiology sciences to form his 'ideal' N|P|K mix of 100 ppm N, 100 ppm P and 200 ppm K. I also very highly doubt Mel Frank, et al., carried out proper experimentation, if any, on cannabis in terms of high vs low P.

Now, decades later most people do not question the claim of high P, at least not until recently (past couple of years), especially found within this thread. I feel such is classic logical fallacy of at least (1) "Appeal to Common Practice"; (2) "Appeal to Authority"; (3) "Appeal to Belief"; (4) "Appeal to Popularity"; and (5) "Appeal to Tradition" ...

As some here have suggested (YS, mullray, etc.), higher P during later flowering may be beneficial, and they may very well be correct. However, I feel that is a separate issue than the claims of Mel Frank and those who do (and have) happily drink the 'Kool-Aid' from Mel Frank, without questioning where it came from. Mullray made a good point about dogma and ignorance ("Dogma is the mother of all ignorance"), which I think applies well to this post.

Just my 2cents.

 

[YosemiteSam]

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

I personally like to keep it below 100 ppm...but I would not disagree with Spurrs numbers.

When you go to a K:N ratio of 2:1 there is a strong temptation to use K2SO4 as a source for K...but it brings with it a shitload of S. Right now I am simply using MKP and KNO3 to satisfy my K. That means less CaNO3 but I make the Ca up with Metalosate Ca.

Additionally if you want to maintain a Ca:Mg ratio of 2:1 you end up using quite a bit of SO4 that way (MgSO4)...so you gotta watch that also.

Currently I am waiting on a shipment of KSilicate. Once I get that I will be able to cut back on the MetCa.

My overall ratios this grow are going to be 1.5:variable:3:2:1 NK:Ca:Mg. That should fix the Ca/Mg problems and we will see what we see yield wise.

 

[YosemiteSam]

a little trich porn

a little trich porn





When your fan leaf stems are honestly sticky...your P might be right.

or your genetics might be good...but that is not as much fun to argue about.

 

[spurr]

View attachment 118714

View attachment 118715

When your fan leaf stems are honestly sticky...your P might be right.

or your genetics might be good...but that is not as much fun to argue about.

 

[DonkDBZ]

I am trying to find a KISS method of hit some nice ratios. I am currently using spurs 5/5/5/5 with Roots excel and GO Bioroots in Veg. DTW coco/perlite and loving it. Just tired of having so many nute bottles.

CNS-17 flower @20ml gallon
121N 53P 252K 121Ca 30Mg 69S

adding 5ml gallon sweet bumps the MG to 53Mg and 99S

any thoughts?


my flora stuff is running out so try and to get flower nutes here in a week

 

[DonkDBZ]

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.



O

I have doing the same thing plugging away. The only downside of earth juice micro was it does not list a S value for all the sulphates it uses

 

[Overthinker]

I could be way off(as I do not know how to calculate the elemental ppm of different compounds), but I don not think that it would contribute very much sulfer at all, as the only sulfide with any significant value is the Mg-sulfide. The guranteed analisys only states .5% Mg.

Earth Juice Microblast
Magnesium 0.50%; Boron 0.02%; Cobalt 0.0005%; Iron 0.10%; Manganese 0.05%; Molybdenum 0.0005%; and Zinc 0.05% in an organic base. Naturally buffered for assured plant absorption. May be watered in or used as a foliage spray. Use 2 tsp. Earth Juice Microblast / gallon of water.

Ingredients: Kelp meal, magnesium sulfate, borax, cobalt sulfate, ferrous sulfate, manganese sulfate, sodium molybdate and zinc sulfate.
The Cobalt, iron, Mn, and zinc are are in such low amount I cant imagine it raising the S much at all. I am sure one of the more enlightened folks around here could confirm this.
BUT what is the point, that cns looks like a pretty solid 'kiss'.
possibly another source of Mg ofther that epsom/sweet would allow a bit more Mg without pushing the S too much.

@all,
is there a good refernce where one can look up salt compounds to find out how much elemental ppm they contribute to solution?

 

[DonkDBZ]

you can plug the numbers into hydrobuddy to figure it out. but guessing that only source of magnesium is epsom it probable has around .7% S

I was too busy thinking about how to be lazy and use cns or sensi bloom to be KISS. But if I wanna mess with GH 3 part and EJ microblast I could probable make something.


Spurr do you run your recipe throughout bloom or do you ever spike Your K levels up?

I know how you don't like pure flowers but......if trying to raise K lvls and keep P low.....since it takes like a year for the P to to be available it sounds like a great way to raise just K.

 

[poipu79]

without considering w/w or w/v

.5%=.005g or 5mg or when useed in g/L or ml/L 5ppm Mg

2 tsp / 10 ml per semi gal same as 2.64 ml/L

sooo 5ppm x 2.64 = 13.20 ppm Mg

...poipu

 

[Overthinker]

Awesome, thanks poipu, I still dont understand how to figure out whether a fert is using w/w or w/v?

without considering w/w or w/v

.5%=.005g or 5mg or when useed in g/L or ml/L 5ppm Mg

2 tsp / 10 ml per semi gal same as 2.64 ml/L

sooo 5ppm x 2.64 = 13.20 ppm Mg

...poipu

I do think however that Donk was worried about the S that comes along with the Magnesium sulfate. So how does one figure out if which the .5% G.A. of Mg provides, 5ppm of 13ppm of mag?
and how much S?

Thanks, O

 

[poipu79]

you can plug the numbers into hydrobuddy to figure it out. but guessing that only source of magnesium is epsom it probable has around .7% S
.

hi overthinker...^^^this seems about rite

 

[poipu79]

It should be stated on the label whether it is %w/v or %w/w

hi mullray... like the rest of i am mixxing dry salts so have not had do deal with the diff between ww and wv
have read the thread and really appreciate your contribution and others YS in particular ...anyway back to lurking

...poipu

 

[YosemiteSam]

I am trying to find a KISS method of hit some nice ratios. I am currently using spurs 5/5/5/5 with Roots excel and GO Bioroots in Veg. DTW coco/perlite and loving it. Just tired of having so many nute bottles.

CNS-17 flower @20ml gallon
121N 53P 252K 121Ca 30Mg 69S

adding 5ml gallon sweet bumps the MG to 53Mg and 99S

any thoughts?


my flora stuff is running out so try and to get flower nutes here in a week

I would add the Sweet. Without it you are in danger of getting a Mg deficiency. Every time I have gone much below 1/2 the Ca for my Mg number trouble has followed.

S would be a little high but that won't affect you as much as low Mg.

 

[spurr]

I am trying to find a KISS method of hit some nice ratios. I am currently using spurs 5/5/5/5 with Roots excel and GO Bioroots in Veg. DTW coco/perlite and loving it. Just tired of having so many nute bottles.

CNS-17 flower @20ml gallon
121N 53P 252K 121Ca 30Mg 69S

adding 5ml gallon sweet bumps the MG to 53Mg and 99S

any thoughts?


my flora stuff is running out so try and to get flower nutes here in a week

The problem with one bottle ferts, or even two bottle ferts, is they lack high degree of customization ...

I would suggest using something akin to Epsom salt, instead of Sweet (for Mg and less S than found in Sweet). As well as dropping CNS-17 to 15 ml/gal and adding a silicon product (for Si and K) providing ~30-60 ppm Si (up to about 80 ppm, max, IMO). That is only two bottles and one box/bag (i.e., Epsom salt), a bit more KISS than the 6 bottles you are now using (granted, the last two bottles listed in your current mix aren't used for plant nutrition, per say).

Here is 15 ml/gal CNS-17 (thanks Carl for the numbers) along with some Epsom salt and ProTeKt ... Si is really important to add IMO:

(approximate from 15 ml/gal CNS-17, 3 ml/gal ProTeKt and 1 g/gal Epsom salt)

• Total N = 137 ppm
• NO3 = 131 ppm
• NH4 = 6 ppm
• P = 40 ppm (you could add some monoammonium-phosphate (MAP) to increase P if you wish, or DAP too)
• K = 182 ppm
• Ca = 128 ppm
• Mg = 49 ppm
• Si = 35 ppm
• S = 84 ppm (IMO this is too high, I like to keep it < 80 ppm)
• Mn = .22 ppm
• Mo = .02 ppm
  • NO3:NH4 = 21.8 (this is too high IMO, esp. if one is using Co2. If using Co2 it's better to reduce the ratio due to issues of NO3 vs NH4 and impact on increased Co2 ability to keep Pn [rate of photosynthesis] high over weeks/months of growth. A ratio less than 8 is not a good idea in most cases, esp if the ammoniacal N is not all NH4. I have tested a ratio of 10 and it worked just fine, now I'm using ~13 but I plan to test 8 in the future.)
  • NO3:S = 1.56
  • P:S = 0.48
  • K:Ca = 1.42
  • K:Mg =3.71
  • Ca:Mg = 2.61
  • K|Ca|Mg =3.7|2.6|1

That said, if you add 2.5 ml/gal CalMag+ and 0.25 g/gal Epsom salt to the CNS-17 (at 20 ml/gal) your final mix would be better vs 20 ml CNS-17 and 5 ml Sweet. I.e., more Ca and less S, as well as slightly more NO3 and NH4, however, the ratios of K:Ca and K:Mg and relativity of K|Ca|Mg are better with 20 ml CNS and 5 ml Sweet:

(approximate from 20 ml/gal CNS-17, 2.5 ml/gal CalMag+ and 0.25 g/gal Epsom salt)

• total N = 132 ppm
• P = 53 ppm
• K = 252 ppm
• Ca = 143 ppm
• Mg = 44 ppm
• S = 77 ppm
  • NO3:S = ? (what is the NO3 ppm?)
  • P:S = 0.69
  • K:Ca = 1.76
  • K:Mg = 5.73
  • Ca:Mg = 3.25
  • K|Ca|Mg = 5.7|3.3|1 (this is kind of high, I like to use around 3|2|1 or 4|2|1)

P.S. I know you're trying to go KISS, but if you have an itching to try something may I suggest giving my current test mix a try?

• 5 ml GH Micro
• 5 ml GH Grow
• 7 ml GH Bloom
• 5 ml CalMag+
• 2.5 ml ProTeKt
• 0.5 gram Epsom salt

my 2 cents ...

 

[YosemiteSam]

I like to do all of my calculations in grams per gallon.

For epsom salt (MgSO4 and some water) 1 gram mixed in 1 gallon of water provides 25 ppm Mg and 33 ppm of S.

So if you know Earth Juice has .5% Mg...and it all comes from epsom salt (not totally true because of the kelp, but it will provide minuscule amounts) then you can simply apply the ratio 33/25 times .5 equals .66% S.

Not all salts are exactly the same...for example KSilicate can be all over the map. So there is no universal list of ppms for salts. You kinda have to look at what is available to you and calculate them for the specific salt you are using. You can also use Hydrobuddy or Custom Hydro's nute calculators to help or to provide answers for salts already in their databases.

edit...and for the record Spurr nailed it. Those trichs are off a freak f2 Deep Chunk x Haze by Tom Hill. My guess is the entire plant may yield 1/4 ounce...but it is a mind blowing 1/4.