A series of standard fluids, characterised in terms of their steady shear and extensional behaviour, was investigated for the behaviour when atomised through a series of matched throughput agricultural spray nozzles. The results show that there are complex, but qualitatively predictable, interactions between the rheological properties of the liquids and the atomisation behaviour. Further, it is clearly demonstrated that low concentrations of very low molecular weight additives may have profound effects on the spray pattern produced by typical nozzles.