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Capitalize on SO4’s Versatility
SO4 pelletized gypsum is a versatile and flexible sulfur fertilizer, which makes it a convenient sulfur source for ag retailers to inventory in storage and growers to use on-farm. SO4 can not only be used on any crop, it is flexible when it comes to what time of year it can be applied and with what tillage practices it can be paired.

Application Timing
Sulfur is needed by the crop throughout the growing season, highlighting the importance of using a sulfur source that will meet this need.

SO4’s sulfur release allows it to be applied at different times without concern for leaching like other, very soluble sulfur sources. Fall, spring or summer applications are all good choices, with a preference toward fall due to less time constraints. Spring or summer are great options as crop needs begin to ramp up.

In the spring, SO4 can be utilized pre- or post-emergence. Many growers apply it pre-emerge, but a growing number are applying it post-emerge (topdress). SO4 topdress can assist with in-season sulfur deficiency and is often blended with nitrogen.

Product Placement
Broadcast, band/strip-till or starter are also application options with SO4. We have more and more dealers using SO4 in the strip-till environment with great success.

Placement depth and subsequent tillage should be considered based on soil conditions. We recommend surface application for broadcast, with a light tillage pass (field cultivator or soil finisher) afterwards being acceptable but not required. Positive effects on the seed germination zone is the goal and tilling too deep or aggressively will result in the SO4 being too deep in the soil profile. Placement depth when strip-tilling is usually 6” or more but having the product in a band tends to mitigate some of the challenge from placement depth.