||Gypsum (Calcium Sulfate - CaSO4) is one of those rare materials that performs in all three categories of soil treatment: an amendment, conditioner, and fertilizer. Soil conditioners, such as gypsum, are seriously undervalued compared to fertilizer usage. Gypsum can help break up compacted soil. Soil compaction can be prevented by not plowing or driving machinery on soil when it is too wet. The compaction in many, but not all soils can be decreased with gypsum, especially when combined with deep tillage to break up the compaction.