Keep Sulfur in Mind When Making Fertilizer Decisions

We know there are essential elements for plant growth. Sulfur is one of them, but there are two forms of sulfur. Taylor Purucker, crop nutrition lead for the Mosaic Company, talks about the two types of sulfur.

“There are 17 specific nutrients that plants cannot live without. Sulfur is one of those. What an essential nutrient is if a deficiency occurs, that deficiency has to be corrected in order for the plant to continue to grow and produce yield. In agriculture, we commonly use two different forms of sulfur. There’s sulfate, which is an immediately available form that the plant can take up. The other form that we commonly use is elemental sulfur. This isn’t something that a plant can take up. It has to oxidize to an available form, and this does take time, but what it does do is it provides mid-to-late-season sulfur needs for the plant when used in the right scenario.”

He talks about how plants take up sulfur.

“Plants take up sulfur through the roots primarily by mass flow. What that means is that the roots will take up sulfur with water. Now, the challenge with that is that sulfate is a mobile ion and so as it’s potentially being taken up with water, if it’s in the soil solution, it is subject to leaching. That’s where something like elemental sulfur comes into play. Elemental sulfur is not water soluble; the plant can’t take it up, and it won’t leach. And what it does do is it provides slow-release form of sulfur that provides mid-to-late-season needs. It’s important to recognize is that this oxidation process does take time. It can take several weeks or months, potentially, but when used in combination with sulfate, it can provide season-long availability.”

That process is important to keep in mind when making fertilizer decisions.

“It’s important to keep these processes in mind when making fertilizer decisions because plants require sulfur throughout the entire growing season. Today’s corn hybrids and soybean varieties –  and this is true for any crop – is that they take sulfur all the way up until they mature, and it’s at a pretty steady pace. For example, corn takes up about 50 percent of sulfur during vegetative growth and about 50 percent during reproductive growth. So, it’s important to have a season long supply of sulfur MicroEssentials is a phosphate fertilizer by the Mosaic Company that provides both sulfate and elemental sulfur, which are two forms to provide season-long sulfur availability.”

He says now is the right time to begin planning a crop nutrition program for next year.

“Fall is a great time to purchase and apply fertilizer, but again I think it’s important to keep in mind that plants require sulfur throughout the entire growing season. Having a form of sulfate early in the growing season allows plants to take up the form of sulfur than it needs. Elemental sulfur is a slow-release form that provides a mid to late season availability. So ,it’s important to keep in mind different forms of sulfur and how to integrate that into your crop nutrition program.”

Growers can speak with their local retailers to learn more about Mosaic’s performance fertilizer products, biologicals, and anything else that would work best in their fields. More information is also available at