This is a question for a medical growth in a big 3'x3'x1.5' no till container Indoor with the objective to have a very clean product.
I'm struggling to make any calculus with organic soil amendments.
I'm in Europe. I use products from local supply, Terralba, BioBizz and Ecothrive and I try to compare with Build a Soil recipes to ensure that I'm not under or over doing it.
I could find detailed NPK ratios for most products but it raises so many questions…
If I understand well, these are the mass ratios of plant available Nitrogen, Phosphorus, Potassium molecules * 1000 (Kg/Ton).
Sometimes I see ppm, what means * 1,000,000. But usually when there are no other indications it is 1000, right?
Now, organic amendments are made available to the plant over time, with the action of micro organismes.
So, what does this NPK actually mean?
Is it the whole quantity of NPK that will be made available to the plant over weeks or years?
If we are speaking about the predicted NPK available over time, we are missing a rough estimate of the delivery timeframe.
Is it the current quantities of plant's available NPK in the soil?
If so, we are missing information about future delivery.
Of course, I understand that the delivery rate depends on micro-organisms activity, soil PH… Also the plants play a key role in the regulation of microorganisms activity at the roots.
I have seen a study about the nitrogen delivery over time of different organic amendments. It showed a lot of variation. Guano made available most of it's N in following weeks, while compost had a very slow release rate and it seems that it would take months.
I keep hearing that compost has NPK values between 3 and 5. But I have seen some analysis and the available parts at this time are very small. I see values between 0.01 and 0.5.
This has huge implications in my attempt to make any calculus to benchmark soils preparations.
If I count with NPK values on the boxes, the vast majority of the NPK of mixes, such as Coot Mix, comes from compost. There is really no point bothering with other dry amendments NPK at this point.
But if I count with the analysis of currently available NPK, compost only accounts for half of the available NPK, the other half coming from dry amendments.
However this is once again not so simple because the dry amendments NPK will also be released over time. There is a huge difference between P from bat guano that is quickly available and P from rock phosphate that will be available over years.
With this level of complexity and so few information available, it seems to be impossible to make any calculus without spending lots of time getting rough estimates of currently available nutrients and delivery over time.
What do you think about the different points raised there? Do I miss something?
What would be your approach?
I'm struggling to make any calculus with organic soil amendments.
I'm in Europe. I use products from local supply, Terralba, BioBizz and Ecothrive and I try to compare with Build a Soil recipes to ensure that I'm not under or over doing it.
I could find detailed NPK ratios for most products but it raises so many questions…
If I understand well, these are the mass ratios of plant available Nitrogen, Phosphorus, Potassium molecules * 1000 (Kg/Ton).
Sometimes I see ppm, what means * 1,000,000. But usually when there are no other indications it is 1000, right?
Now, organic amendments are made available to the plant over time, with the action of micro organismes.
So, what does this NPK actually mean?
Is it the whole quantity of NPK that will be made available to the plant over weeks or years?
If we are speaking about the predicted NPK available over time, we are missing a rough estimate of the delivery timeframe.
Is it the current quantities of plant's available NPK in the soil?
If so, we are missing information about future delivery.
Of course, I understand that the delivery rate depends on micro-organisms activity, soil PH… Also the plants play a key role in the regulation of microorganisms activity at the roots.
I have seen a study about the nitrogen delivery over time of different organic amendments. It showed a lot of variation. Guano made available most of it's N in following weeks, while compost had a very slow release rate and it seems that it would take months.
I keep hearing that compost has NPK values between 3 and 5. But I have seen some analysis and the available parts at this time are very small. I see values between 0.01 and 0.5.
This has huge implications in my attempt to make any calculus to benchmark soils preparations.
If I count with NPK values on the boxes, the vast majority of the NPK of mixes, such as Coot Mix, comes from compost. There is really no point bothering with other dry amendments NPK at this point.
But if I count with the analysis of currently available NPK, compost only accounts for half of the available NPK, the other half coming from dry amendments.
However this is once again not so simple because the dry amendments NPK will also be released over time. There is a huge difference between P from bat guano that is quickly available and P from rock phosphate that will be available over years.
With this level of complexity and so few information available, it seems to be impossible to make any calculus without spending lots of time getting rough estimates of currently available nutrients and delivery over time.
What do you think about the different points raised there? Do I miss something?
What would be your approach?
