Calculating NPK

Running GH trio and trying to work out exactly what NPK i'm throwing in at specific stages of plant growth.

I'm stoned and more than likely overbaking this / fucking everything up but bear with me here.

Lets take the standard accepted formula for veg: 3 parts Gro to 2 parts Micro to 1 part Bloom (3-2-1).

Gro has an NPK of 2-1-6.
Micro = 5-0-1
Bloom = 0-5-4

3 parts Gro gives 6-3-18. 2 parts Micro = 10-0-2, and of course 1 part Bloom = 0-5-4.

Added together this is an NPK of 16-8-24.

Am I done good, or am I today's worst student???

If it is right, how is an NPK this high in K good during veg? I thought NPK ratios of 3-1-2 were good for veg?

Pile on here and ruin me if you like, this is driving me crazy.

I'm going with uh....too stoned ofa student....

3 parts grow doesn't give you 6-3-18, it gives you 2-1-6 dispersed over a larger volume.

But maybe I'm too stoned too...

Yeah i'm pretty sure I shouldn't be multiplying the base NPK's by the quantity in parts. So how else is it done?

Perhaps as weighted percentages? I can't do that either...

Anyone?

NP WHAT??? worm-castings.

I'm kind of confused as to what exactly you're trying to figure out. You want to know the exact amount of N, P, and K? Like part per million or how many mililiters of each per gallon of water or what?
Just follow your nute guide? Or whatever. Then mess around with amounts on a cpl different plants....see how they react....
Idunno....

GreenSanta said:

NP WHAT??? worm-castings.

Click to expand...

Thanks yes thats definitely what we're talking about here.

ME: what is 9 x 3?
YOU: Botswana

MoMoGrows said:

I'm kind of confused as to what exactly you're trying to figure out. You want to know the exact amount of N, P, and K? Like part per million or how many mililiters of each per gallon of water or what?
Just follow your nute guide? Or whatever. Then mess around with amounts on a cpl different plants....see how they react....
Idunno....

Click to expand...

Hmm, good question. I've forgotten what i'm doing.

Move along, nothing to see here.

I think your getting lost on parts.
Want to have some fun? Call the maker and ask them!!......How do you base your nutrient at it's NPK value to water volume? 5ml to a gallon is the 2-1-6 or what?

Dr. Who said:

I think your getting lost on parts.
Want to have some fun? Call the maker and ask them!!......How do you base your nutrient at it's NPK value to water volume? 5ml to a gallon is the 2-1-6 or what?

Click to expand...

Dr. Who said:

I think your getting lost on parts.
Want to have some fun? Call the maker and ask them!!......How do you base your nutrient at it's NPK value to water volume? 5ml to a gallon is the 2-1-6 or what?

Click to expand...

Your Ans. sounds "more right" than the multiplying.

A.K.A. Overgrowem said:

Your Ans. sounds "more right" than the multiplying.

Click to expand...

The thing is, some list a value as bottled.
Some list a value as the feeding chart gives. Say x amount to a gallon is the listed value.

ruwtz said:

Thanks yes thats definitely what we're talking about here.

ME: what is 9 x 3?
YOU: Botswana

Click to expand...

Yet it was the best answer.

Dr. Who said:

The thing is, some list a value as bottled.
Some list a value as the feeding chart gives. Say x amount to a gallon is the listed value.

Click to expand...

Yes, my newtz lists NPK as bottled, I have no exp. with NPK listed any other way.

A.K.A. Overgrowem said:

Yes, my newtz lists NPK as bottled, I have no exp. with NPK listed any other way.

Click to expand...

Dbling the charted amount - gives you dbl the amount your delivering to the plant......
Thing is this is rather a moot issue - Follow the makers charting and adjust as needed.....

Powdered nutrients are generally reduced in amounts used to be delivered at appropriate npk values that the plant will use properly and not be overnuted....

Example: 24-8-16......I would weight the amount suggested by the maker and do my mixing by weight, to reduce to a value delivered daily to 3-1-2.
Higher amounts can be used, you just feed less and add plain watering between feedings.....I wouldn't myself go higher then 6-2-4 ....
The smaller the fert grains the better too.

I'm less fucked up today so I can straighten out what I was trying to do.

We know that aiming for NPK ratios of 3-2-1 in veg and 1-2-3 in flower will deliver results, and I have seen NPK regimens tweaking this further for specific growth phases, for example early veg 4-2-3 (week 2) and flower swell (week 6) 1-5-4.

I fully appreciate there is no hard and fast rule or a set cannabis feeding chart, but still I believe there is some merit to these tweaked regimens and therefore was looking for a conversion of these into bottle ratios for GH Flora Trio. The same could be done for any three part "Gro Micro Bloom" nute product, but GH is what I use.

So, taking the given NPK values of the bottles, can we hit a specific NPK target to tell us the quantity we need from each bottle? Say we want NPK 3-2-1, how much Gro do we need for this as a ratio against how much Micro and Bloom we also need to reach 3-2-1?

I know my math was off and I went at it like a bull in a china shop. You can see above I was adding all the bottle NPK's together, which probably isn't the right start at all.

It is not a complicated idea, one which i'm sure smarter people have faced and solved before now.

There has got to be a rudimentary calculation for this, no?

I still think I was in the right ballpark.

Calculating the NPK that plants see when using a three part system is pretty simple, and is likely how the Lucas formula and other designed regimens can be arrived at.

An accepted formula for veg of 3 parts Gro to 2 part Micro to 1 part Bloom (3-2-1).

Gro has an NPK of 2-1-6.
Micro = 5-0-1
Bloom = 0-5-4

3 parts Gro gives 6-3-18. 2 parts Micro = 10-0-2, 1 part Bloom = 0-5-4.

Added together = 16-8-24

Divided by 3 = 5-2.6-8

Seems high on K for veg, wouldn't you say? This is why i'm starting to think the GH Flora NPK's aren't very applicable to cannabis, or at best I need to reshuffle the numbers to find a better fit.