Milorganite and Potassium

Update (11/15/2018): Milorganite has updated their label and now shows a 6-4-0 N-P-K breakdown. The page I linked to below has also been updated to reflect their new specifications and no longer shows the 0.5% potassium. It is my personal opinion that this potassium is still in the product even though the website doesn’t show it. You can view the version of the specifications page from the time I originally wrote this post by clicking here.

I have heard some people say that Milorganite doesn’t contain potassium (K).  This is simply not true.  There is actually 0.5% potassium!  The reason the N-P-K on the bag reads 5-2-0 is that it gets rounded down to zero.  Because the actual breakdown is 5-2-0.5, that leaves you with 1.8LB of nitrogen, 0.72LB of phosphorus, and 0.18LB of potassium per 36LB bag!

Here is the full breakdown if you are curious:

N-P-K Analysis 5.0% Total Nitrogen (N)
2.0% Available Phosphate (P)
0.0% Potash (K-typically is about 0.5%)
4.0% Iron (Fe)
Typical Micro-nutrients 0.58% Sulfur (S)
0.68% Magnesium (Mg)
0.045% Zinc (Zn)
0.022% Copper (Cu)
0.133% Manganese (Mn)
Trace amounts of Boron (B) and Molybdenum (Mo)

The same information can be found on Milorganite’s website here.


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