Why do we need to use fertiliser?
Fertiliser replaces the nutrients removed when produce from the land is harvested. Fertiliser allows soils to maintain or increase plant growth and provides essential nutrients for animal health. It is a vital part of New Zealand's agricultural and forestry industries. These industries are a major source of income for New Zealand through the export of meat, wool, timber and horticultural produce to offshore markets.
It is estimated that without fertiliser use, New Zealand's soils would be capable of supporting less than half, and possibly as low as 25% of the animals grazed or crops grown. Such a drop in agricultural production would have a devastating effect on the country's economy.
New Zealand soils in their natural state are typically acidic, and low in phosphate, sulphur and some trace elements. Since modern agricultural practice began, New Zealand farmers have been supplementing the soil's natural nutrient level with fertiliser, to improve the land’s production potential.
The most common fertiliser used has been superphosphate but in more recent times this has been blended with potash, sulphur and trace elements.
The gradual enhancing of New Zealand's soils has transformed their stock grazing and crop growing capacity. Generally, New Zealand's soils have reached a state where it is possible for farmers to maintain current nutrient levels. However, if fertiliser application was lower than the requirements of crops or pasture, the soil would revert to a lower animal or crop carrying state.