The Importance of Sulfur in Plant Development

Sulfur plays a key role in the use of nitrogen in plant growth. The question is often asked if sulfur is just as important as nitrogen in crop development. Most corn producers (4 in 5) will tell you that it is just as important and apply sulfur each year. Less than half of soybean producers will apply sulfur each year. Corn and soybeans need 16 essential nutrients to grow and complete their life cycle.

Crop production doesn't need all the elements in the same amount. That is the reason we break down the elements into three categories of Primary elements (C, H, N, O, P, & K), Secondary elements (Ca, Mg, & S), and Micro elements (B, Cl, Cu, Fe, Mn, Mo, & Zn). Plant growth is limited by the nutrient that is in the shortest supply.

Sulfur's importance is a key part of three amino acids used to make proteins. Just because the number of pounds of sulfur isn't higher doesn't mean the nutrient is less important. Until recently, most have not worried about sulfur due to the fact they were receiving free from the atmosphere through power plant emissions. Stricter rules over the last few decades have greatly reduced the amount emitted
by power houses.

Knowing where you stand with sulfur in crop production is to pull tissue samples and check the nitrogen to sulfur ratio. In corn production the ratio of nitrogen to sulfur should fall between a range of 10-to-1 to 12-to-1. In soybean production the ratio should be around 17-to-1. Nitrogen is still important for soybeans to complete their life cycle.