Superphosphate comes in granules of different sizes. The best superphosphate has granules of 1–4 millimetres in diameter, with about 5% outside this range. The granules collapse on contact with soil moisture and release phosphate rapidly into the soil.
Using this item
This item has been provided for private study purposes (such as school projects, family and local history research) and any published reproduction (print or electronic) may infringe copyright law. It is the responsibility of the user of any material to obtain clearance from the copyright holder.