The sulphur sold by H.J. Baker and its subsidiary, ICEC, is one of the key components used in the creation of fertilizer around the world. The most important form of sulphur for fertilizer is the mineral calcium sulfate. Elemental sulphur is hydrophobic (not soluble in water) and cannot be used directly by plants. Over time, soil bacteria can convert it to soluble derivatives, which can then be used by plants. Sulphur improves the efficiency of other essential plant nutrients, particularly nitrogen and phosphorus. Biologically produced sulphur particles are naturally hydrophilic due to a biopolymer coating and are easier to disperse over the land in a spray of diluted slurry, resulting in a faster uptake.

The botanical requirement for sulphur equals or exceeds the requirement for phosphorus. It is an essential nutrient for plant growth, root nodule formation of legumes, and immunity and defense systems. Sulphur deficiency has become widespread in many countries in Europe. Because atmospheric inputs of sulphur continue to decrease, the deficit in the sulphur input/output is likely to increase unless sulphur fertilizers are used. Atmospheric inputs of sulphur decrease because of actions taken to limit acid rains.