Gypsum vs Lime? Thoughts On Agricultural Gypsum

I recently purchased a bag of what I thought was lime recently to use on trials, only to discover that it was actually gypsum. I included it in the trial anyway out of curiosity, and it got me thinking, why don’t we think about gypsum more often?

Essentially calcium sulphate, gypsum contains two very important elements for crop growth and can do some great things for the soil structure. An important misconception is that gypsum is a type of lime that is not true, it does not neutralize acidity – which can be useful in some situations such as high magnesium, higher pH soils that might be short of calcium but do not need the pH to be increased.

It is very useful on high magnesium clay soils and can help them ‘flocculate’ or make them easier to break down. Sodic soils can be improved too by applying gypsum as the calcium displaces the sodium, which then forms sodium sulphate and leaches through the soil.

Read Frequently Asked Questions on Gypsum here