The Myth of Low N?

[mrbong73]

I still think SUL-PO-MAG is a better choice than epsom salts because of the K profile which is exteremly important during flower. IMO

 

[desertsquirrel]

I agree, K is important. Though its not lacking in the profile. The Epsom did awesome this run.

 

[desertsquirrel]

bump...

 

[desertsquirrel]

No one has anything to add?

 

[Snowblind]

DesertSquirrel Jacks has a new Hydro Herb formula that was just released.

Most people here are not interested in a bunch of numbers....

This new mix is kinda cool here is the breakdown as Ive learned it so far. My numbers might be wrong.

Hydro Herb new one part formula 16-4-17
N=16%
P=4%
K=17%
Ca=4%
Mg=2%

Breaks down to....

1 gram per gallon of water=

N=40
P=4.4
K=35
Ca=10
Mg=5
S= I dont know yet

At 3 grams of Hydro Herb per gallon you would get.....

N=120
P=13.2
K=105
Ca=30
Mg=15
S=?? I dont know yet


The ratio is....9-1-8 a very interesting ratio. You switch to a higher P formula in bloom and alternate with the lower Hydro herb.....

This mix will need epsom salts 2 grams would give you aprox...
Hydro herb 1 gram + 2 grams of epsoms equals
Mg=67
S=64 plus whatever extra S that I dont know is in the formula yet.

Im getting a water sample and getting it checked out to see how many ppm of Ca is in my tap water. I think its around 25 ppm of Ca where I live.

You can add P in flower by using ph down from Gh because its made with phosphoric acid which is used as P by your plants...I need to figure a conversion of say 5 ml of gh ph down into a ppm amount of Phosphorus.

Anyone know?

 

[epicseeds]

I really would like to start to make my own nutes, over the past year I have read this and that about high p low n and vice versa. here is my current belief:

you want 3 "shocks" of high P. which exact weeks/stages these should be at i do not know, but suppose one during flip, one during peak, and one for ripe.

i feel that K also plays an important role. people have been raving about shooting powder which is a 0-1-2 formula i believe. shooting powder is used weeks 6-8 so perhaps high K is essential here?

x-5-4/x-5-3 seems to be best for mid bloom as well as early bloom


has anyone who has been following these homemade nutrient threads found a really complete coco nutrient profile? I have been using CNS17 Ripe as a base (1-5-4) for bloom and think it's time for me to get more advanced. I would like to make a really complete and scientificly sound nutrient regimen for coco. Any help?

 

[Capulator]

Can you help me understand the tissue analysis? couldn't the plant just be storing the N in its tissue, and not actually using it? Kind of like foraging for a possible drought?

 

[I_Love_THC]

Hello, friends! Great thread! I've been looking for something like that ever since I had an idea during a lucid dream...
So, give more P during the first half of the flowering and more K during the second, is that it? Also, use Epsom salts, OK.
BUT, I have a problem, because of my small brain:
You're speaking in PPM and what I need to estimate is mg/dm3.
I have a Humic Extract (last bottle of 2% C, I'll get the one with higher C for the next run) and it says:

Macro:

N - 4610
P - 2200
K - 20600
Ca - 626
Mg - 240

Micro:

Fe - 198
Mn - 8,4
Cu - 1,0
Zn - 10,9

Ph - 7.07
EC - 21.53 ms/cm

Could anyone help me convert and understand?
Also, I'm using high-P Guano (2-15-2) and high-K palm-tree ashes (0-3-14). I decided to combine them to get a booster and use the Humic extract as a vitalizer... So, now I'm at day 35 and it's time for me to give them water today. Tomorrow or the day after that, I'll be boosting with the last high-P dose and then start giving more Humin (also proportionally high-K, but wanna know how high it is, haha) and maybe give lower doses of the palm-tree ashes, but more often. Oh, that reminds me - why do I have to give the ashes every two weeks? Is it like slowly absorbed? Or do the guys at Guanokalong just see the old 1:1 (PK, like 13/14) formula more useful? If you know the reason WHY I should use it only once every two weeks, then I can see if I'd be able to use it more often as a high-K source...

I'm also preparing a nettle-extract - just saw that somewhere, but never read the whole thing and don't really know what it is rich in... So, I just know that I should use it after the sixth week of 12/12 - any other tips on it?
And, I have a seaweed+kelp-extract, too - only don't know how often I can use it - any help on that, too?

Sorry if I'm bothering - just wanna know, hehe.
Peace and Blessings to all of you, friends!

 

[HG23]

Yea I'm a little confused as well DS. Can you just take a tissue sample, get it analysed and find out with kinds of elemental nutrient concentrations a specific strain is looking for at that period in the growth cycle? It seems like you're talking generally, about all strains, but I don't see any mention about where these tissue samples came from. Also isn't mag. sulfate MgSO4.H2O or something? Does that H2O matter?

 

[Seamaiden]

No one has anything to add?

I've been repped with a question regarding the 6%Ca product I have. It's made by or called BioLink.

 

[Apophis]

Yea I'm a little confused as well DS. Can you just take a tissue sample, get it analysed and find out with kinds of elemental nutrient concentrations a specific strain is looking for at that period in the growth cycle? It seems like you're talking generally, about all strains, but I don't see any mention about where these tissue samples came from. Also isn't mag. sulfate MgSO4.H2O or something? Does that H2O matter?

The test analysis data on page 1 of this thread doesn't state what species of plant is being tested but does state analysis was done by a company in Canada, so i am assuming they are testing hemp and not marajuana. Hemp does not have the synthesis for thc like marajuana does, therefore macro-nutrient requirements would be much different.

As someone who has done thousands of plant tissue tests, let me try to explain the method and scope. To determine what levels of nutrient applied is taken up and utilized, you can not analyse accurately in a soil or organic medium. The most important factor in tissue testing is control of nutrient applied, and this is very difficult in soil/organic because of the lack of precise measurement of what nutrients are in root zone. The best method would be plants grown in hydro where measurements are as close to exact as possible, and if using a solid media or for plants grown outside, the media should have a CEC value as close to 0 as possible(like washed sand). 99% of these tissue tests are done with a NIR spectrometer, which requires that the plant material to be tested is completely dried and ground to a fine dust. Ground plant material is hit with a beam of light, reflected back and wavelength is compared to a database that determines levels of elemental nutrient(even though it is not in elemental form inside the plant).

Tissue testing marajuana poses several complications because nutrient has to be applied and then NEW growth must occur before you can take a sample to be tested. All previous growth MUST be ignored . . . see how difficult this becomes? In veg it is not so difficult, you can start off with a 6 inch specimen in a hydro "bucket", mix known and measured nutrient solution, allow plant 1 week growth and then cut tissue samples from new growth above 6 inches. After first sample is taken and tested you are left with a hacked up plant that needs 1 or 2 weeks recovery and then a week of new growth again before next sample can be tested. This makes it even more difficult in flower especially in the first few weeks of flower when buds are small, tissue samples taken would basically ruin plant, you could not get regular samples on a schedule. Could be done with many plants in a system that shares all nutrient solution like an UC system, taking samples from new plant each week that way you could get analysis on a weekly schedule: veg 1,2,3,4 flower 1,2,3,4 etc.

Just taking a random tissue test is not going to tell you what the plant wants more or less of in regards to macro or micro nutrients. It would take a couple of years and lots of space and patience(oh yeah and money too) to determine optimum nutrient requirements at the various stages of marajuana.

 

[Elite Nugs]

Maybe Im retarded.... but wouldnt it be more simple to put a plant in a hydro system with fresh nutes... then have the nutrient water in the reservoir tested (water analyst) every week, at the beginning and end of each reservoir change.

For example, if you start at 100ppm of Nitrogen and at the end of the week, your at 75ppm of nitrogen, then you'll have a pretty good idea as to what your plants are actually taking in during that particular week.... No??

Would that not work?? Not that simple???

 

[desertsquirrel]

Sorry i have been really busy guys. ill be around soon.

 

[Jalisco Kid]

You completely forgo using any A? Do you taper off from normal feeding at beginning of flower, to no A at 4 weeks, or do you just turn it off all at once at four weeks?

Week four on all strains, or is that for a specific time-frame (8 week strain, 10 week strain, etc.)?

I forgot about posting here. I would cut off the a all at once. We run 10 week plants. Plants store and move N around the plant. JK

Leaf samples give you a base line for what you are doing. It is not hard nor expensive. And sometimes you need to take out a whole plant for a sample. If you want to control what you do instead of guessing or following a crowd you gotta do what you gotta do. JK
Cardy meters help

 

[Apophis]

Maybe Im retarded.... but wouldnt it be more simple to put a plant in a hydro system with fresh nutes... then have the nutrient water in the reservoir tested (water analyst) every week, at the beginning and end of each reservoir change.

For example, if you start at 100ppm of Nitrogen and at the end of the week, your at 75ppm of nitrogen, then you'll have a pretty good idea as to what your plants are actually taking in during that particular week.... No??

Would that not work?? Not that simple???

Not retarded . . . good question.

That gives you only half of the equation, which is very important, but without tissue testing how do you accurately determine what level of macro-micro nutrients the plant is using relative to your nutrient solution going in? Observation alone? What happens if you use a solution next time with 200ppm of N? 300ppm or 400ppm? How do we know which ppm level of any nutrient is optimum? For example: perhaps yield and thc production would be increased by elevating Mg from 1% to 3% inside the plant while N is kept at a 5% level and what solution do you need to attain an increase of Mg by 2% inside the plant? The plant will take up whatever is in the aqueous solution you put the roots in, whether it starves to death or burns to a crisp. Tissue testing will identify optimum levels and ratios relative to what you are applying. Testing on both ends along with observation of yield, growth rates, and thc production(can always test this too) are all required if you are serious about solving "the myth of low N" or the common belief that mj "needs" more Ca and Mg or whether Si has any benefit at all to mj etc.

Considering the 15 elements required for synthesis(not just N) that come in a bottle or bag(the other 3 we dont have to buy), i believe it is obvious there would be a fair amount of testing needed. In 2000 i charged 30 bucks per tissue test and did anywhere from 18 to 72 a day, 5 days a week per client. This number of testing tapered down over a 3 week to 2 month period after a nutrient program was submitted and applied to correct stress or poor nutrient levels and ratios. Just did a search for aqueous nutrient solution testing at an average of $90 per test and dry tissue testing at an average of $60 per test. It will get expensive, better to just buy a dual sample NIR and do it all in house.

Unless there is plenty of money and time, not really worth it.

The whole point of tissue testing is to determine what level and ratio of macro-micro nutrient inside the plant are optimum for cellulose/carb synthesis(growth rate/yield) and in mj the synthesis of THC(what we are all after). It also(this has already been done) determines what nutrient "compounds" are most available to the plant so you know which nute companies are bullshitting you.

 

[H3AD_CAS3]

It also(this has already been done) determines what nutrient "compounds" are most available to the plant so you know which nute companies are bullshitting you.

Please elaborate...

 

[albone3000]

To keep it simple, how about flora nova grow:

7-4-10
boils down to
1.75-1-2.5

maybe add some liquid kool bloom at the end (since i already have it). I might give this a try.

what would be something I could easily bump the N up a little with? flora micro maybe, but I dont already own that. I do have blood meal though.

 

[purpleberry]

I always thought canna coco A/B had to much N, I think its like a 5-3-2 , My friend uses it and he always takes a week longer to finish and his plants dont want to color up on the purple stuff. But he does get huge nugs, that for some reason dont always equal huge yields.
I always run the veg 1-2 weeks in so they dont yellow out on me. I probally shoudlnt do this on short busy indicas, it does make them leafy lol Works good on the OG that stretchs for 3 weeks.
Differeent strains are going to want differnt programs, Thats why im narrowing it down to a few and working them til they put out how i want.

 

[Snowblind]

Apophis what elemental N-P-K ratio do you like best for growing cannabis?

To keep it simple, how about flora nova grow:

7-4-10
boils down to
1.75-1-2.5

maybe add some liquid kool bloom at the end (since i already have it). I might give this a try.

what would be something I could easily bump the N up a little with? flora micro maybe, but I dont already own that. I do have blood meal though.

This is not the correct way to think about this!

I forgot about posting here. I would cut off the a all at once. We run 10 week plants. Plants store and move N around the plant. JK

Leaf samples give you a base line for what you are doing. It is not hard nor expensive. And sometimes you need to take out a whole plant for a sample. If you want to control what you do instead of guessing or following a crowd you gotta do what you gotta do. JK
Cardy meters help

JK in flower what is the max ppm of P you feed when you do your boost?

 

[Jalisco Kid]

Besides week one where i might go high with P I still am only at 80 ppm I normally ride around 55-60 ppm. JK
My bios do not care to go over 70 PPM