Calcium fertilisation restores the pH level of soil. Calcium is an essential nutrient that provides strong cell walls and a solid, resistant crop. It is especially important on heavy clay soils, providing a good cell structure. Calcium sulphate is recommended when pH level is higher than 7.

We offer a range of minerals for agricultural applications, including:

  • Bentonite
  • Brussels earth
  • Calcined natural magnesium oxide
  • Calcium/ magnesium carbonate
  • Calcium carbonate
  • Calcium sulphate
  • Caustic calcined magnesium oxide
  • Dolomite
  • Iron carbonate
  • Magnesium hydroxide
  • Manganese dioxide
  • Zeolite

Our fertiliser brands include:

Dolokal Extra PG

Produced from natural magnesium rich limestone, which is dried and ground for potting soil. This product is RHP certified.


Produced from carefully selected, naturally occurring magnesium hydroxide. The standardised quality of SECUROC B is guaranteed by means of an ISO 9001 certified quality management plan. The chemical composition of raw material and product is closely monitored and particle size kept within a narrow variation.

OzMag Fert, OzMag 1000

The OzMag brands are calcined natural magnesium oxides manufactured from Queensland Magnesia’s high quality cryptocrystalline magnesite deposit. Being non-toxic, pale pink powders and granules, they are characterised by high magnesium content and neutralising properties.

Our Dutch and Flemish customers will find more information about soil neutralisers and their value at:


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