A wide range of organic ligands are found in the rhizosphere. Two important groups are low-molecular-weight organic acids (LMWOAs) and siderophores. We know that LMWOAs and siderophores coexist in the rhizosphere and it has been proposed that they interact, but it is not clear what controls this. Such knowledge gaps undermine biofortification efforts. In this study test the hypothesis that pH and ionic strength gradients make it possible for LMWOAs and siderophores to function synergistically during micronutrient cycling in the rhizosphere.