Physical Description:
Superphosphate is made by reacting finely ground phosphate rock with sulphuric acid to convert the insoluble mineral to a plant available form. Superphosphate contains phosphorus and sulphur in a ratio of 1 to 1.16. When applied at a rate to meet P requirements, the sulphur requirements will also be met in the majority of situations. The colour varies from brown to dark grey with each rock type.
Uses:
Superphosphate is an ideal fertiliser for capital or maintenance applications. It is mainly used as a maintenance fertiliser, providing a pool of soil solution P for pasture. It is also ideal for pastoral development and arable/horticultural situations where immediate responses are required.
Benefits:
Superphosphate also contains Sulphur in the readily available form of sulphate for plants to take up. This makes it ideal for low fertility and cropping situations. The Calcium in Superphosphate can be important in some horticultural and hill country situations where it is uneconomic to use lime.
Application:
Spreading rates for Superphosphate vary depending on soil,farm type and climatic conditions. It is recommended not to be spread at rates of over 1 tonne/ha. Your field officer is available to help you with the Superphosphate rages that will be best for your farm. Superphosphate generally mixes well with other products, but cannot be mixed with Urea or this will cause the mix to harden.
Storage & Handling:
As with most solid fertilisers, Superphosphate can be stored over a season as long as it is kept in a cool, dry, well ventilated area.
Source:
Phosphate rock is currently sourced from Togo and Morocco.
Additional Information:
Fluorine and Animal Health: All products manufactured from phosphate rock (including MAP and DAP), contains flourine. These can cause flouride poisoning if enough fertiliser is directly ingested by stock. Ideally livestock, particularly pregnant and lactating animals, and animals under stress, should not be reintroduced for at least 21 days, or after 25mm of rain have fallen after fertiliser has been applied. This recommendation will minimise but not eliminate the risk, and farmers should ensure they have uncontaminated feed available if there is a problem.
Fertilisers and Germination: Germination damage may occur if fertiliser is placed in close proximity to seed. In general, the drier the soil, the smaller the seed and the higher the application rate, the risk of germination damage is greater. Superphosphate is much less likely to cause damage than products releasing ammonium nitrogen, such as Urea and some Cropmaster products.
Soil Acidification: Soil acidification is caused by the interaction of climate, soil and biological processes. Superphosphate is not an acidifying fertiliser because it contains most of its P in the form taken up by plants, as well as sufficient calcium to balance out any acidifying effect caused by leaching of sulphur. The utilisation and production of pasture, the decay of dead plant material to form organic acids, nitrogen fixation and the leaching of nutrients such as nitrate all contribute to soil acidification.
MSDS:
Superphosphate