Superphosphate

Best applied in Autumn/Winter for root crops. It is quicker acting than bone meal and has a slightly acidic action on the soil. Rate of use: 2-4 oz per sq.yd (68-136g per sq.m)

Phosphorus Pentoxide (p2o5) 18% (P7.9%) Soluble in Water and Neutral Ammonium Citrate.