To compare iron fertiliser formulations for lupin on an alkaline soil.

• Growth of lupins receiving chelated iron was greater than those receiving iron sulphate when grown on an alkaline soil (pH 8.7 H2O).
• Experiments were conducted on the adaptation of lupin species to these soils and to develop techniques to increase grain production from the most extensively grown species, Lupinus angustifolius. 
• No rhizobia strains were found to be superior to WU425 on alkaline soils. It was found that cultivars of L. pilosus and L. atlanticus yielded more than the narrow leaf lupin varieties when grown on alkaline soils. 
• High numbers of Bradyrhizobium lupini (>1000/g soil) were found in all 19 soils sown only once with inoculated lupins 1-17 years previously. The addition of iron to these soils increased lupin dry matter production but not grain yield.