NPK

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bankcee

Well-Known Member
can some one really explain NPK ratios. I understand what is needed at what point in the life cycle of cannabis. High N for veg and High PK for flower. and vice versa.

but I notice so many different ratios in different ammendments. 1-1-1, 5-1-1, 3-16-1, 2.5-0-2.5 etc etc..

like is that a "per serving" ratio per container how is this measured? is there any ideal ratio to be used? if I mix all this into a soil with a 0-0-0 ratio then what is the NPK ratio that is in my soil? and how long does this ratio of nutrients last? when does the soil go completely depleted of nutrients?

idek if this is all stupid useless information I'm seeking. but I wanna know. lol

any help is appreciated.
 
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bankcee

Well-Known Member
so like does any of the really apply to organics? as I am trying to stay organic.

cause then that leads me to my other question, how do super soils get people through veg and flower. by dumping all this shit into them. no pun intended. lol

also how can I tell what ratio is in my soil if I'm adding 7 different ammendments one says 3-16-0 the other says 4-3-1 and 1-0-0, 2.5-0.5-2.5, 1-0.1.-1, 6-1-3, 0-0-0.2

what npk ratio is in my soil? and on average what how many weeks of veg should my N get me and how many weeks of flower should my PK get me? what variables? I wanna learn. like how many cups per cf of soil were ammended with this mix?
 
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T.H.Cammo

Well-Known Member
bankcee said:
so like does any of the really apply to organics? as I am trying to stay organic.
Of course it does, N.P.K. is N.P.K. regardless of where it comes from.

cause then that leads me to my other question, how do super soils get people through veg and flower. by dumping all this shit into them. no pun intended. lol
Yes, exactly! There is enough nutrients in there to last throughout the entire grow.

also how can I tell what ratio is in my soil if I'm adding 7 different ammendments one says 3-16-0 the other says 4-3-1 and 1-0-0, 2.5-0.5-2.5, 1-0.1.-1, 6-1-3, 0-0-0.2
It's all just a matter of math. N.P.K. numbers represent the percentage (by weight) of Nitrogen, Phosphorous and Potassium in any nute or fertilizer. You need to get an individual index on every ammendment by figuring the ratio and weight you are adding, of each product. Then you need to find the total weight of all the nutes you added and adjust the individual ratios according to how much weight you added of that particular product. A product with an N.P.K. of 4-3-1 may only be 1/20th of the total amount of the ammendments (by weight) so it only gets a 5% share (.2-.15-.05) of the overall N.P.K.. Then you add all these (adjusted) ratio amounts and divide by the number of ingredients you added. Simple, huh?

what npk ratio is in my soil?
Can't really tell without knowing how much weight you added of each ingredient. I'm not gonna do the math, you figure it out!

and on average what how many weeks of veg should my N get me and how many weeks of flower should my PK get me? what variables?
Plants use N.P. and K. in all stages of growth, the simplest plan is to use equal amounts of all three and use enough to last the entire grow. Another way to start out is just use one of the "hundreds" of soil recipes you see all over the place - and then start to experiment a little.

I wanna learn. like how many cups per cf of soil were ammended with this mix?
Click to expand...

I don't understand this question. Most ingredients I use will say "use "X" amount per cubic foot of soil".
 
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pseudobotanist

Well-Known Member
Alright young grasshopper...
Wether you use organics or synthetics, both contain nitrogen, phosphorus, and potassium.

Organic fertilizers provide you with npk in an organic form. This form of fertilizer isn't readily available by your plant, microbes in your soil will convert this fertilizer from an organic form into an Inorganic form slowly and over time. This is how organic growers can last thru veg without the addition of extra fertilizers, however this isn't always the case.

Synthetic ferts however are readily available for your plant to uptake. This is why nute burn can be experienced with synthetics and why it's rarely experienced with organic grows.

Any other questions?
 
Dr. Who

Dr. Who

Well-Known Member
To further address your question on how the NPK lasts through the run on organics.
When you mix in your amendments. Some are fast release and some are slow release....A balance of these will get you through the grow run

Example:
Bird, Bat or any Guano, poop or animal droppings are FAST release (be very careful with high P guano's. You can burn easy)
Alfalfa, Neem, Karanja meals along with Nettle and Comfry leaves are SLOW release forms of nutrition.

Blood meals are fast release.
Bone meals are slow.

Greensand is very slow release and is a "down the road" amendment for re-used soil. It can take months to even a year before it comes into play. (Great as a "no-till" soil starting amendment.)

Glacial rock dust or your mineral amendments are there long term. They are both fast and slow release as they last for a year before you have to re-amend them into re-using soils. You should note that Azomite is used quickly and needs re-amending

Dolomite, Oyster shell, eggshell and your Ca sources can and do vary for usefulness. Powdered sources should be re-amended with every re-use of soil, while crushed, prilled or the course forms of these will last longer but, it is still prudent to add some powdered form of Ca at every soil recharge...

The trick is to balance between these......Mixing amounts of each and then amending with that mix is a simple way to get everything you need.

That is a brief example of these things and their availability...

This is a chart I have had for a long time and still find useful.....While not exactly complete, it's easy to fill in the cracks on the web.

http://www.lundproduce.com/N-P-K-Value-of-Everything.html

That help?

Doc
 
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bankcee

Well-Known Member
Dr. Who said:
To further address your question on how the NPK lasts through the run on organics.
When you mix in your amendments. Some are fast release and some are slow release....A balance of these will get you through the grow run

Example:
Bird, Bat or any Guano, poop or animal droppings are FAST release (be very careful with high P guano's. You can burn easy)
Alfalfa, Neem, Karanja meals along with Nettle and Comfry leaves are SLOW release forms of nutrition.

Blood meals are fast release.
Bone meals are slow.

Greensand is very slow release and is a "down the road" amendment for re-used soil. It can take months to even a year before it comes into play. (Great as a "no-till" soil starting amendment.)

Glacial rock dust or your mineral amendments are there long term. They are both fast and slow release as they last for a year before you have to re-amend them into re-using soils. You should note that Azomite is used quickly and needs re-amending

Dolomite, Oyster shell, eggshell and your Ca sources can and do vary for usefulness. Powdered sources should be re-amended with every re-use of soil, while crushed, prilled or the course forms of these will last longer but, it is still prudent to add some powdered form of Ca at every soil recharge...

The trick is to balance between these......Mixing amounts of each and then amending with that mix is a simple way to get everything you need.

That is a brief example of these things and their availability...

This is a chart I have had for a long time and still find useful.....While not exactly complete, it's easy to fill in the cracks on the web.

http://www.lundproduce.com/N-P-K-Value-of-Everything.html

That help?

Doc
Click to expand...

hell yeah that helps makes a lot of sense now.
 
B

bankcee

Well-Known Member
pseudobotanist said:
Alright young grasshopper...
Wether you use organics or synthetics, both contain nitrogen, phosphorus, and potassium.

Organic fertilizers provide you with npk in an organic form. This form of fertilizer isn't readily available by your plant, microbes in your soil will convert this fertilizer from an organic form into an Inorganic form slowly and over time. This is how organic growers can last thru veg without the addition of extra fertilizers, however this isn't always the case.

Synthetic ferts however are readily available for your plant to uptake. This is why nute burn can be experienced with synthetics and why it's rarely experienced with organic grows.

Any other questions?
Click to expand...
yeah I got questions for days. now how do you tell what ratio you have in your soil? is it as simple as adding all the N numbers adding all the P numbers and K numbers and the sum of each is the NPK ratio you have in your soil?
 
greasemonkeymann

greasemonkeymann

Well-Known Member
bankcee said:
so how do these soil gurus no what ratio they're running at a given time. and also how long it will last? I assume the second question is just through trial runs and COE
Click to expand...
the ratio doesn't matter.
it's the availability of the nutrients, forget the NPK numbers.
also it's highly recommended to NOT abandon nitrogen during flowering, it's a hydro myth that you need high p and k with low nitrogen.
trial runs will teach you a lot, but at your point in experience i'd suggest just listening to an experienced organic grower that has done this many times.
 
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bankcee

Well-Known Member
greasemonkeymann said:
the ratio doesn't matter.
it's the availability of the nutrients, forget the NPK numbers.
also it's highly recommended to NOT abandon nitrogen during flowering, it's a hydro myth that you need high p and k with low nitrogen.
trial runs will teach you a lot, but at your point in experience i'd suggest just listening to an experienced organic grower that has done this many times.
Click to expand...
so what should a good soil consist of? seriously? forget npk numbers? isn't that what is feeding my plant? i know the microherd is doing the work but they are chomping on what I'm putting into my soil.. no?

isn't that valuable info? if making a super soil? what is a good 1-1-1 recipe? or forget that too? I'm just trying to understand.
 
greasemonkeymann

greasemonkeymann

Well-Known Member
bankcee said:
so what should a good soil consist of? seriously? forget npk numbers? isn't that what is feeding my plant? i know the microherd is doing the work but they are chomping on what I'm putting into my soil.. no?

isn't that valuable info? if making a super soil? what is a good 1-1-1 recipe? or forget that too? I'm just trying to understand.
Click to expand...
ok, so first, a supersoil isn't the best technique, so i'd look elsewhere.
As far as npk goes, you are overthinking it.
organics are not like hydro chems where you feed it 100% of what you are feeding it, organics is more like having a food supply there at all times for the plant to take what it needs.
Make a soil with slow, medium, and fast release properties of everything the plant needs, that's where, yes, in fact NPK is important, but not in the way you are thinking.
you don't add up the numbers, because they don't break down and release themselves 100% all at once.
make sense?
For example, fast release stuff is guanos, blood meal, and such.
medium would be like neem meal, kelp meal, alfalfa meal, and maybe shrimp meal.
slow release would be crab meals, bone meals, and most minerals.
you want to source your nutrients wisely, or you'll have deficiencies later
 
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bankcee

Well-Known Member
that's makes a lot more sense. gotta break it down for me a little further sometimes. lol but yeah I get you now. and as far as a "food bank" in a super soil, it is possible to burn correct? so anyone in ss type grows what is over doing it? what is a hot recipe that would be overkill for say a three week old plant. and also for a month old plant? can I throw a bunch of shit into soil and give it some good diversity and the microherd will just eat and convert whatever comounds the plant needs for growth? or is it not that simple?

kinda like humans? we eat til we're full and we stop? or will the microherd just keep breaking down the compounds til I see a nute burn?
 
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