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Tasmania Australia

Hi, This might be a basic silly question but i have to ask.
In bulk fertilizer bags, like the 1 tone bags you can get, dose anyone know what they bulk them out with?
To explain what i am trying to figure out, say i have a bulk mix of say 7-7-7 and another bulk mix of 14-14-14.
To my understanding, and i could most likely be incorrect here,
but with the 7-7-7 mix or the 14-14-14, it is a ratio of N-P-K, by percentage weight in the fertilizer mix.

But i am thinking that they must make up the rest of the bulk bag mix with another product, is this correct and dose anyone know what that product is?
Was just trying to figure it out as i can't see how you can get a 1 tone bulk bag of 7-7-7 and also a 1 tone bag of 14-14-14 without something else being in there to get these two mixes.
Any information would be greatly appreciated.
Cheers.

9/22/2015 11:53:47 PM

Germany

These numbers only tell you the percentage of N/P/K contained in this fertilizer (reported as N, P2O5 and K2O, respectively). The fertilizers won´t contain elemental N, and they contain neither P2O5 nor K2O but they will contain salts which contain these elements (N could be ammonium, NH4(+), or nitrate, NO3(-); P will in most cases be some kind of phosphate, PO4(3-); K will be some kind of potassium salt which contains K(+) together with a counter ion). The fertilizer companies are not forced to mention all the ingredients, even though some of them could also be helpful fertilizers themselves, such as sulphate, SO4(2-), which is one of the common counter ions for potassium. Sometimes the fertilizers contain magnesium, Mg(2+), calcium, Ca(2+) and other ions as well, they just don´t need to be listed. In case of magnesium the fertilizer could contain epsom salts, the formula of which is MgSO4*7(H2O), in case of such salt hydrates a significant amount of the mass of this compound comes from water of crystallization, which is contained in the solid state structure of this compound.
There are probably many ways of mixing a 7-7-7 fertilizer, some of them use "fertilizer only ingredients", some of them could use a "fertilizer only" mix of a 14-14-14 and then add 50% of any kind of non-NPK and non-fertilizer material. That said, using half as much of the 14-14-14 could perhaps give different results than using the 7-7-7, because the 7-7-7 might contain other ingredients which are helpful and which aren´t contained in the 14-14-14. Without a detailed analysis of the fertilizer, or without the company telling you what´s inside, there´s no way to tell what´s inside because of the many possible ways of mixing such a fertilizer.

9/23/2015 4:13:34 AM

Hanson Ma

Wow I think my brain just exploded. I knew some of that stuff but great explanation of NPK ratios.

9/23/2015 5:48:32 AM

Germany

A simple example is 0-0-50 vs. 0-0-60. Pumpkin growers love 0-0-50 and most of them won´t recommend 0-0-60 (some of them made the experience that the 0-0-60 made their pumpkin split). Even though one might argue that one could use 0-0-60 but using only 83% (because this would give the same amount of potassium added to the patch), there must be a different thing about these fertilizers which causes their different effects on the plants and fruits. The only difference between these two fertilizers is the counter-ion, which is chloride in case of 0-0-60 but sulphate in case of the 0-0-50. This difference between the anions probably makes the largest contribution to the different effects observed with these fertilizers, whereas the slightly different K-content probably plays a minor role.
A mix of 83% of 0-0-60 and 17% of an inert material also give a fertilizer which would have to be labelled "0-0-50", but I´m quite confident that many AG growers agree that this "0-0-50" would have different effects on the pumpkin plant than the 0-0-50 which consists of pure potassium sulphate.

9/23/2015 6:04:44 AM

Tasmania Australia

Cheers, yes i can see what you are saying with the Primary Cations Calcium ++, Potassium +, Sodium +, Hydrogen +
And the primary Anions Phosphorous ans Sulfur.

Only really picked 7-7-7 and 14-14-14 as it was a bit easier tying to say what i meant without confusing anyone.
But would be interesting trying to find out what they do use, as you mentioned, could be non fertilizer mix or fertilizer only mix.
But cheers Pumpking, i think i am on the right track.
Appreciated.

9/23/2015 6:55:04 PM

Bethlehem CT

Good question Bluesilver!

9/24/2015 5:44:14 PM

Central NY

This winter Ima go back to hikeschool and dig in on some of this stuff...evry post I read I get it more and more...I think pumpking and countryboy need to get together and write another pumpkin book...

9/24/2015 9:13:58 PM

Tasmania, Australia

Hey blue silver, also good idea to be aware of the chemical identity the nutrients are supplied as. eg. N can be as nitrate, urea, ammonium etc. each will take different times to be bioavilible to the plant, and some forms may burn or muck your pH up. Go see your local ServAg shop. Ive found them to be very helpfull with advice on the correct ferts.
cheers Andrew

9/26/2015 8:58:55 PM

Tasmania Australia

Cheers, Yes, working on getting the soil in near perfect balance as i can.
SerAg have been pretty helpful.

9/28/2015 3:10:14 AM