Fertilizer!

Someone on Crop Talk asked what Potassium Sulfate is and how to use it as a fertilizer.  Several of us joined in the discussion and offered what we know.

Potassium Sulfate is 0-0-40-17 analysis and a product of some process used in industry.  It typically comes from Utah so the freight increases the price, although Candadian Murate of Potassium is not much closer to me.  It is just usually more widely available and less expensive.

Potassium is an excellent source of Potassium and Sulfur for crops.  It is just not available at every dealer like Murate of Potash is.  "It's odd how this old-fashioned name remains in use! Muriate comes from Muria, the Latin for brine. Muriate of potash is potassium chloride containing between 50 and 60 per cent potash. It was deposited eons ago by ancient seas and should be considered a natural product, blessed by organocultists, but it is not. Its chlorine content passes off rapidly when applied to soil.


As explained under soil organisms, however, muriate of potash is harmful to certain beneficial bacteria. Some authorities think sulfate of potash makes a better potash fertilizer."

Another good thread included the discussion of another primary plant nutrient, Phosphorus  Here was my reply to his question:

".4 row, Jeff the foliar dud(e) has the fancy explanation why you may not have enogh P. This is where the tissue test comes in, you should have found P Low to Deficient with a tissue test in that corn at tassle and I think you would have.


I didn't see see that you put the lime on and that would help over time. If it is rental ground, 200 lbs of pellet lime in your dry mix has helped me avoid P and other deficiencies that crop year and I have picked up as many as 20 bushels doing it.

When it calls for 74 units, I about have to double that to come close, that would be over 200 lbs of MAP or DAP and still the conversion is lower because it needs 1500 lbs of lime.

Theoretically you could convince yourself that 10 gallons of 10-34-0 would be enough to feed the P needs but in reality it probably wasn't.

I say get the ton of lime on now, it's cheap here compared to P and I would want the ground 3 more years and double the lime rate because that soil will probably also be slow at changing Ca Mg and P.

Not a long post at all and a great question. How much does it take to resolve a known deficiency? In my experience, it can easily and often takes more nutrient to get the tissue test to say Sufficient in the needed nutrients and when those go up, others start showing deficiency like Zinc, Manganese or Boron.

Great question and I hope you can learn from this experience and grow better crops in the future. "

Farmers have a lot of questions and though we are all busy right now, it is good to address as many as we can!  It looks like our Indian Summer is coming to an end tomorrow and we will be down 30 degrees for daily temperature next week.

Maybe this wasn't Indian Summer.  Maybe it is coming yet in November?  Remember how warm last winter was?

Ed