Silica + Potash Silica (Organic) Silica is another word for Silicon and, in plants, it is present in amounts equivalent to, or higher than, elements like Calcium, Magnesium or Phosphorus. Silica's important role in plant nutrition is now being extensively researched. Recent experiments show that plants deprived of Silica are structurally weaker, more prone to pest and disease attack, and are more susceptible to heavy metal and salt toxicities among other things. Silica has also been recognised as important in human health with researchers including Louis Pasteur predicting the importance if silica to human health. Silica, in rocks, commonly occurs as the mineral quartz and in the soil it exists in 3 forms: reactive, colloidal & suspended particles (ie sand) Reactive Silica dissolves in water to form silicic acids which are the forms in which Silica is taken up by plants. Once Silica is incorporated into a cell of a plant it is immobile and cannot be redistributed around the plant. Therefore if all tissues are to benefit from its presence, it needs to be in constant supply.Silica also assists in the uptake of nitrogen, potassium, zinc, magnesium and other elements. Regular use of Silica Foliar Spray ensures a constant supply to all your plants and vegies and should be used in addition to your usual fertilising programs.