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Understanding NPK values

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Re: Understanding NPK values

Post by GMO »

Viz wrote:By adding inert liquid such as pure water to any mixture you will dilute that mixture.
Thanks for that buddy

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Re: Understanding NPK values

Post by GMO »

Imma bump this discussion a little. but maybe we can sway the convo towards NPK ratios for different stages of growth

So my understanding is that during vegetative growth a plant will require a NPK ratio heavier on the N side at like 3-2-1 NPK because the nitrogen is used to create leaf tissue at this stage and P and K and less required in volume but are still required as K is the driving force for metabolism.

Moving into flower the ratio is usually reverse to 1-2-3 is because the majority of the structure development is complete, but a low level of N is require to continue metabolic reactions which are related to photosynthesis. as mention the K is driving the rate of metabolic reaction and the P is drive the development of seed, flower and fruit associated with reproduction phase

obviously this is a general over view but we have lots of little tricks to shift the ratio to suit our needs

what kinda ratio shift do you use and how do you plan the timing of nutrient changes

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Re: Understanding NPK values

Post by weedabix »

I just read this thread and while I don't have an answer to the growing (I am a total noob) I understand your initial question as follows:
Do the NPK values represent ratios (ie. 1-2-3 would be the same as 2-4-6) or do they relate to concentrations (ie. twice the amount of 1-2-3 are the same as 2-4-6 if diluted by 1l of water)? Did I get that question right?
According to wikipedia, the convention is that these numbers represent weight percent of the elemental N and the oxides of P and K (US) and the UK allows to additionally state the elemental weight percentages of all N-P-K in parentheses. So it does refer to total concentrations in the fertiliser and if you were to use 2g of 1-2-3 in 1l it would be the same as 1g of 2-4-6 in 1l - roughly... in theory we'd have to use (roughly again) 998ml and 999ml respectively but I don't think that's the accuracy necessary here. There might be quite a difference between 1ml and 1g of fertiliser but if you really wanted to you could calculate that as well.
https://en.wikipedia.org/wiki/Labeling_of_fertilizer

Now this is all I can add to this and I am looking forward to hearing how to use those numbers now!

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Re: Understanding NPK values

Post by GMO »

weedabix wrote:I just read this thread and while I don't have an answer to the growing (I am a total noob) I understand your initial question as follows:
Do the NPK values represent ratios (ie. 1-2-3 would be the same as 2-4-6) or do they relate to concentrations (ie. twice the amount of 1-2-3 are the same as 2-4-6 if diluted by 1l of water)? Did I get that question right?
According to wikipedia, the convention is that these numbers represent weight percent of the elemental N and the oxides of P and K (US) and the UK allows to additionally state the elemental weight percentages of all N-P-K in parentheses. So it does refer to total concentrations in the fertiliser and if you were to use 2g of 1-2-3 in 1l it would be the same as 1g of 2-4-6 in 1l - roughly... in theory we'd have to use (roughly again) 998ml and 999ml respectively but I don't think that's the accuracy necessary here. There might be quite a difference between 1ml and 1g of fertiliser but if you really wanted to you could calculate that as well.

Now this is all I can add to this and I am looking forward to hearing how to use those numbers now!
I'm really really pleased Bixy mate. You've grasped it exactly how I hoped

My theory is that we as growers who use a base nutrient ie canna A+B that we know the NPK ratio and with the minor additions of other nutrient ie PK 13/14 that we can have complete control of the NPK ratio we are feeding at each stage... assume we measure volume of nutrients used and not just the EC

In the same line of thought, if we know the NPK ratio that we are aiming to create that we can look at any NPK ratio on a bottle (ignoring the feed guide) and easily decide if that nutrient will help us reach the NPK ratio we are aiming for. This also should really help if we ever need to change nutrients suddenly there isnt the worry of shock because of changing nutes, we can just match the ratio no matter what bottles we are using to reach the values we want

Does that make sense?

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Re: Understanding NPK values

Post by weedabix »

I think this totally makes sense. The producers of bottled nutrients might argue though that 1. These macronutrients make up only a small part of their amazing recipe that of course contains dragon scales and bokoblin horns in undisclosed ratios. 2. The amount of salt only matters if these can be taken up by the plant and if mixed incorrectly (e.g. by mixing A+B before diluting it) - it might form solids that precipitate from your water and form salts that can't be taken up.
They are probably over exaggerating but there is a truth to it.

And I think this is where it becomes tricky and in the end it's down to growers experience to then see what the plant needs, and in what quantities before shit hits the fan! And that's where my wikipedia/google skills won't help me but rather reading people's diaries on here, listening and reading to suggestions by experienced growers, and growing myself and figuring out what the plant needs.

The link to the wikipedia page also contains some numbers for common salts and organic fertilisers - which I found quite interesting.
I am using an "organic nutrient" by biobizz - and it doesn't say anything! I'd say its a mix of molasses and something fishy judging by its smell - but that's about how much I know about it!

I think the next grow for me will be a coco grow - I love data and numbers (it shows doesn't it) and I would like to see the comparison to my current soil grow. In this I am running two different strains at the same conditions and soil and one is doing great and the other one had some major issues with some nute lockout or something similar. This shows how complicated things are - especially when in soil where there are microbes and complicated things like that.

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Re: Understanding NPK values

Post by GMO »

weedabix wrote:I think this totally makes sense. The producers of bottled nutrients might argue though that 1. These macronutrients make up only a small part of their amazing recipe that of course contains dragon scales and bokoblin horns in undisclosed ratios. 2. The amount of salt only matters if these can be taken up by the plant and if mixed incorrectly (e.g. by mixing A+B before diluting it) - it might form solids that precipitate from your water and form salts that can't be taken up.
They are probably over exaggerating but there is a truth to it.

And I think this is where it becomes tricky and in the end it's down to growers experience to then see what the plant needs, and in what quantities before shit hits the fan! And that's where my wikipedia/google skills won't help me but rather reading people's diaries on here, listening and reading to suggestions by experienced growers, and growing myself and figuring out what the plant needs.

The link to the wikipedia page also contains some numbers for common salts and organic fertilisers - which I found quite interesting.
I am using an "organic nutrient" by biobizz - and it doesn't say anything! I'd say its a mix of molasses and something fishy judging by its smell - but that's about how much I know about it!

I think the next grow for me will be a coco grow - I love data and numbers (it shows doesn't it) and I would like to see the comparison to my current soil grow. In this I am running two different strains at the same conditions and soil and one is doing great and the other one had some major issues with some nute lockout or something similar. This shows how complicated things are - especially when in soil where there are microbes and complicated things like that.
Awesomely valid points about "organics" and the interaction with microbes... that's gonna be a bit of a different topic maybe but a very interesting one that I think is well worth discussion.

If we use this as a hydro/coco discussion of inert medium it is maybe a simpler concept? I again have to completely agree that micro nutrients blends are possibly very important, the term micro nutrient refers to only needing a very small volume but they are still massively essential for growth. I would be purely assuming but I would think that the vast majority of base nutrients have these covered without the addition of too many micro nutrients boosters

I just gotta add that I really enjoy these kinda discussion, to have different perspectives can really help understand things better that any one person may not have considered

translated from the bongo of the canna jungle


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Re: Understanding NPK values

Post by 2-Scoops »

I not read link but will do in a bit @GMO. But my understanding of it all works is, well lets talk pk 13/14, its only that in bottle, so lets say 80% of that bottle is water and rest pk13/14 in mix, so lets say that same bottle was 40% water and rest pk its would be pk26/28, its only those ratios whilst in bottle basically. You wanna be looking for npk ratios with higher numbers if you want more bang for your buck and i read dry ferts is where its at in that case, bottled ferts are a real con as we all know most of it is just bloody water. Another way to ,look at it is if its pk13/14 in bottle then mix it with 10 liters of water and its gonna be pk3/4. Well that`s how i always understood it all if i understood it in first place.
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Re: Understanding NPK values

Post by GMO »

jimmi2scoops wrote:I not read link but will do in a bit @GMO. But my understanding of it all is say lets talk pk 13/14, well its only that in bottle, so lets say 80% of that bottle is water and rest pk13/14 in mix, so lets say that same bottle was 40% water and rest pk its would be pk26/28, its only those ratios whilst in bottle basically. You wanna be looking for npk ratios with higher numbers if you want more bang for your buck and i read dry ferts is where its at in that case, bottled ferts are a real con as we all know most of it is just bloody water. Another way to ,look at it is if its pk13/14 in bottle then mix it with 10 liters of water and its gonna be pk3/4. Well that`s how i always understood it all if i understood it in first place.
Yes yes yes jimmi. This is exactly what I'm talking. Like ya say 13/14 as example that's 13% p and 14% k (also as bixy pointed out earlier thats the total chemical weight not just the single element specified).

So we have to tools and knowledge to decide what as you say give you the most bang for your buck. But also allows you to meet your preferred ratios at each stage without too many additional bottles of this and that

translated from the bongo of the canna jungle



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Re: Understanding NPK values

Post by 2-Scoops »

weedabix wrote:
Thu Jan 30, 2020 10:59 am
I just read this thread and while I don't have an answer to the growing (I am a total noob) I understand your initial question as follows:
Do the NPK values represent ratios (ie. 1-2-3 would be the same as 2-4-6) or do they relate to concentrations (ie. twice the amount of 1-2-3 are the same as 2-4-6 if diluted by 1l of water)? Did I get that question right?
According to wikipedia, the convention is that these numbers represent weight percent of the elemental N and the oxides of P and K (US) and the UK allows to additionally state the elemental weight percentages of all N-P-K in parentheses. So it does refer to total concentrations in the fertiliser and if you were to use 2g of 1-2-3 in 1l it would be the same as 1g of 2-4-6 in 1l - roughly... in theory we'd have to use (roughly again) 998ml and 999ml respectively but I don't think that's the accuracy necessary here. There might be quite a difference between 1ml and 1g of fertiliser but if you really wanted to you could calculate that as well.
https://en.wikipedia.org/wiki/Labeling_of_fertilizer

Now this is all I can add to this and I am looking forward to hearing how to use those numbers now!
Yes cock on mukka that is, looking at it in a bit of a same but different way to how i put it in my last post, but both ways achieve same thing and result. :oik!:

Why do they not sell ferts like some tom feeds of lets say 20/20/20 for simple reason theirs not as much cash in it. You could make a bottle of tom ferts go ten times further, prolly only thing needs adding is a spoonfull of trace ellements every once in a while and that`s not called for really, ive seen some really nice grows done with crazy high npk tom ferts, just ask Beefy.

Bigger the NPK ratios further your cash goes put plain and simple in my eyes. 8-)

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Re: Understanding NPK values

Post by 2-Scoops »

GMO wrote:
Thu Jan 30, 2020 12:19 pm
jimmi2scoops wrote:I not read link but will do in a bit @GMO. But my understanding of it all is say lets talk pk 13/14, well its only that in bottle, so lets say 80% of that bottle is water and rest pk13/14 in mix, so lets say that same bottle was 40% water and rest pk its would be pk26/28, its only those ratios whilst in bottle basically. You wanna be looking for npk ratios with higher numbers if you want more bang for your buck and i read dry ferts is where its at in that case, bottled ferts are a real con as we all know most of it is just bloody water. Another way to ,look at it is if its pk13/14 in bottle then mix it with 10 liters of water and its gonna be pk3/4. Well that`s how i always understood it all if i understood it in first place.
Yes yes yes jimmi. This is exactly what I'm talking. Like ya say 13/14 as example that's 13% p and 14% k (also as bixy pointed out earlier thats the total chemical weight not just the single element specified).

So we have to tools and knowledge to decide what as you say give you the most bang for your buck. But also allows you to meet your preferred ratios at each stage without too many additional bottles of this and that

translated from the bongo of the canna jungle
Theirs lots and lots of dry ferts that are made for hydro on fleabay that would last you ten times longer than a bottle of AnB > chempak nu 2 and 4 for veg and bloom come to mind but theirs others specifically for hydro if you look i forgot the ebay sellers name but thinking its my next move GMO. 8-)

Cool thread. :thanks:
Last edited by 2-Scoops on Thu Jan 30, 2020 12:33 pm, edited 1 time in total.

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