The role of Fe oxides on the availability and dynamics of phosphorus (P) is poorly understood in calcareous soils. We ascertained its role in laboratory and plant growth experiments on substrates prepared by mixing calcium carbonate (calcite) sand (CCS, 0.2-0.5 mm) and Fe oxide (ferrihydrite)-coated quartz sand (FOCS, 0.2-0.5mm). Distribution of P into the solid and liquid phases was studied after one, three, six, and ten wetting-drying cycles (WDC) after adding P as KH2PO4at the rate of 0, 5, 10, 20, 50, and 100 μg P g−1to substrates containing 0, 10, 30, 50, 70, 80, and 90% FOCS. Different P levels, WDC and substrate composition had a significant (P< 0.05) main and interactive effect on P distribution between solution and solid phases. There was a significant (P< 0.05) 1- to 8-fold increase in the distribution ratio of P between solution and solid phases with increasing FOCS in the substrate at 10 and 20 μg g−1P. The increase in water-soluble P with FOCS was sharper at 10 μg P g−1than at 20 μg P g−1. In the plant growth experiment, durum wheat (Triticum durumcv. Don Pedro) was grown in substrates containing 0, 10, 20, 30, 50, and 90% FOCS, which received P as KH2PO4at the rate of 0, 6, 12, 18, and 72 μg P g−1. Substrates containing higher proportion of CCS tested higher for Olsen P for the same rate of P application. The same trend was observed for Olsen P after cropping. Substrate composition and P application rate had a significant (P< 0.05) main and interactive effect on growth and P uptake by plants. Phosphorus-Zn interaction due to increased P supply in the soil-plant system depressed plant growth with increasing P application rate at higher proportion of FOCS in the substrate. Concentration of P in plants increased significantly with increasing proportion of FOCS in the substrate. The relationship between plant P concentration and concentration of P in the substrate solution could be described by a Michaelis-Menten equation. At a certain level of Olsen P, plant P concentration increased with increasing FOCS proportion in the substrate. This suggests that Olsen P might overestimate plant-available P in Fe oxide-poor relative to Fe oxide-rich calcareous soils.