The History and Development of Solid Fertilisers in New Zealand
Superphosphate New Zealand’s soils are by and large not naturally fertile, simply because of the low levels of some key nutrients – phosphorus (P) in particular – in the volcanic and sedimentary rocks they have been formed from. Single superphosphate (SSP), made by reacting finely ground phosphate rock with concentrated sulphuric acid, was first produced … Read more