Real meaning of N-P-K?

B

bignugs68

Well-Known Member
So I'm on my 3rd grow. 2 seedlings 1 week old. As prepping my 3gal pot soil I got to thinking. I've seen people use Nature Organics 4-4-4, I've read people using 10-10-10 fertilizer, 2-8-4 for bloom, or wild high numbers like 12-28-22 - miracle grow pellets I used first grow for bloom :p.

And like I got FF tiger bloom, I know it's instant availability more or less. I hope you see where I'm going. We get these numbers which show ratios of what's in it, but how do we know like how much? Is a 2-8-4 liquid nute providing the same as a 2-8-4 nute pellet??? I just feel there should be a better system label. Like avg ppm/day or total ppm/serving ya know? Or am I missing a beat here??
 
medidedicated

medidedicated

Well-Known Member
I think I see what you mean, like what the 4-4-4 is supposed to be, measurement wise? I dont know but Il watch for answers with ya.
 
medidedicated

medidedicated

Well-Known Member
I havent really thought about it using flora trio and maxibloom now. I just assumed it meant parts which I dont understand well. Not very achedemic here.
 
T

Tomatoesonly

Well-Known Member
There's a little more to those numbers when you dig further. I'll mess up the explanation, but the P and K numbers are labeled higher than what
is considered "available" p and k. I think it all goes back to old farming and labeling practices that make no sense to you and me.
There is an actual mathematical percentage of the P and K numbers that lowers them to actual real life normal numbers.
 
medidedicated

medidedicated

Well-Known Member
Yea I was high but then I remembered I asked RIU and noone chimed in but its been slow as we all know. I just thought ok whats 10% of 3 gallons.. Theres no way you put that much h202 (expensive) or that much bleach.

The bleach would just make a giant soap bubble bath barely doing anything. Just all bubbles. I just remembered that and was like yea Im done thinking for the day. Sleepin on it is good.
 
amneziaHaze

amneziaHaze

Well-Known Member
Hmm now i wonder as well i allways fought it was %. But all my life i just looked at veg or flower i want n big rest small or n small rest big hahaha
 
Farmer's Hat

Farmer's Hat

Well-Known Member
Found this.

2-8-4 liquid nutrient and a 2-8-4 pellet nutrient are not providing the exact same thing, despite having the same N-P-K ratio. Here's why:

*Different forms of nutrients:*

1. Nitrogen (N): Liquid - ammonium nitrate or urea; Pellet - slow-release ammonium sulfate or polymer-coated urea.
2. Phosphorus (P): Liquid - orthophosphate or polyphosphate; Pellet - slow-release monoammonium phosphate.
3. Potassium (K): Liquid - potassium nitrate or potassium sulfate; Pellet - potassium sulfate or potassium chloride.
 
B

bignugs68

Well-Known Member
Haha I definitely know what NPK are, microbes, other nutes:iron, calcium, mag, sulphur; all those basics. Its not super important to know for a successful grow, I've just always been a "I want to know why and how it works" not just "this works" kind of people.

After all seems odd to put same amounts 4-4-4 and 10-10-10 in equal pots and have identical results no? Maybe I'll experiment with that next grow. Like I can't wrap my mind around some of these grow journals where in 3 or 5 gal pots people use 20-20-20, or some outrageous 42-10-10 stuff....that should absolutely cause burn and not allow anything to grow, yet people are successful with it.
 
amneziaHaze

amneziaHaze

Well-Known Member
Well as you said slow relese and instant are not the same.allsoo its 42 but he puts 1/3 of recommended amount.... and allsoo some plants eat a shit tone some dont eat anything
 
medidedicated

medidedicated

Well-Known Member
5-15-14 maxibloom. It works so Im just using that no studying further. Its why Im here too could always learn more. I used flora trio which I thought was just paying for water.

I guess if I had a strain that needed a certain npk ratio that would be good to use. But then Id need to know how the mulder chart works which I never have but I have it saved.

That involves chemestry or else lock out. Id read a lot about PH and some about lock out in synergy or what ever its called. From people with phd in chemestry.

So I know more about the ions and how ph is measured but npk I just havent read much on. On messing with that. Im assuming with maxibloom you cannot tweak anything just add calmg if needed.
 
C

cage

Well-Known Member
medidedicated said:
5-15-14 maxibloom. It works so Im just using that no studying further. Its why Im here too could always learn more. I used flora trio which I thought was just paying for water.

I guess if I had a strain that needed a certain npk ratio that would be good to use. But then Id need to know how the mulder chart works which I never have but I have it saved.

That involves chemestry or else lock out. Id read a lot about PH and some about lock out in synergy or what ever its called. From people with phd in chemestry.

So I know more about the ions and how ph is measured but npk I just havent read much on. On messing with that. Im assuming with maxibloom you cannot tweak anything just add calmg if needed.
Click to expand...
It's good practise to start familiarize yourself with the nutrients more and more.
Then it's alot easier to buy the nutrients instead of brands.
And all of it can be applied to different plants and different grow methods.

Like 7CardBud pointed out, there's a small catch with the NPK numbers itself.
Some places the P in the NPK is actually the % of P205
and same for potassium is then often represented as K2O.

As for tweaking maxibloom or any other premixed nutrient solution, you could just add any supplement nutrients like CalNit, MgS or (M)PK powder and
have a better ratios for the specific plant/pheno/growth stage
 
Last edited:
B

bignugs68

Well-Known Member
I imagine it's gonna take me one evening of nerding out on how nutes with big differences in nute numbering produce similar results. Maybe it boils down to the different sources or forms of NPK behind the numbering.

As for the 1/3 statement....
amneziaHaze said:
Well as you said slow relese and instant are not the same.allsoo its 42 but he puts 1/3 of recommended amount.... and allsoo some plants eat a shit tone some dont eat anything
Click to expand...
If that actually had merit then each fertilizer would state "X-X-X" in every 1/4 cup" or something. But it doesn't. Whether I put 1/3 cup in 1gal of soil, or 1/3 in 3gal, or 1 cup in 1 gal, my bag doesn't say anywhere how much = 5-3-3 | Epsoma bio-tone starter plus(I use 1/3 recommended dose). I mean when someone asks what fert you use, regardless of the volume of feet you use, you still quote the NPK.

So does it work like alcoholic drinks? Roughly, in any amount of the fertilizer 5% of material is N, and 3% for both P and K?
 
T

Tomatoesonly

Well-Known Member
bignugs68 said:
If that actually had merit then each fertilizer would state "X-X-X" in every 1/4 cup" or something. But it doesn't. Whether I put 1/3 cup in 1gal of soil, or 1/3 in 3gal, or 1 cup in 1 gal, my bag doesn't say anywhere how much = 5-3-3 | Epsoma bio-tone starter plus(I use 1/3 recommended dose). I mean when someone asks what fert you use, regardless of the volume of feet you use, you still quote the NPK.

So does it work like alcoholic drinks? Roughly, in any amount of the fertilizer 5% of material is N, and 3% for both P and K?
Click to expand...
Dude you come in here asking basic questions and when someone answers correctly, you say "If that actually had merit"???
You are too ill informed on the topic to be telling people their answer is wrong.
There are huge amounts of info from the farming community, think actual food products, that have used these numbers and from which, is how the labeling even began.
 
You must log in or register to reply here.
Top