SO4 Now, AMS Later to Address Sulfur Deficiency

Oct 10, 2022


Sulfur ranks right behind N, P and K for crop health
Sulfur is critical to chlorophyll development and protein creation in most every crop. And while sulfur (AMS) is commonly applied each spring, additional sulfur sources are highly beneficial to plant health and improved yield.
 
Enter SO4, a pelletized gypsum product (mined in northwest Iowa) consisting of 21% calcium and 17% sulfur – sulfur is an essential nutrient that falls in line right behind N, P, and K.
 
SO4 pellets can be mixed with fertilizer or spread alone, and while its calcium is valuable, (especially for alfalfa), the sulfur in SO4 “is the most critical,” said Tim Stelter, Federated’s Osceola location manager. SO4 provides a “season-long source of sulfur … because it is less susceptible to leaching.”
 
Additionally, SO4 is pH neutral. Over time, other sources of sulfur can draw down the pH, but “SO4 won’t increase or draw down the soil pH,” said Stelter.
 
Based on data provided by Federated’s upper Midwest soil lab, fields in Minnesota and Wisconsin are sulfur deficient, and crops will benefit from applying sulfur. “Everything wants sulfur,” he said – corn, soybeans, alfalfa, and other crops as well. SO4 spreads well, isn’t dusty, and is a “high quality product,” he said.
 
Check soil sulfur levels with regular soil testing. (Note: soil tests include sulfur analysis by request, for an additional fee.)
 
Combined with timely AMS applications, SO4 can further improve grain quality and increase yields. And, it’s cost-effective. As Stelter said, “SO4 is just one more tool in the [crop management] toolbox.”
 
Talk to your Federated Agronomist to learn more about SO4 and schedule applications this fall.
 

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