Phosphorus (P) deficiency is a major constraint limiting sustainable rice cultivation in sub-Saharan Africa—partly due to the deeply weathered soils that have low pH and contain high P-fixing Fe and Al oxides. Soil texture also affects P availability and use efficiency. In this study, we evaluated the combined effect of soil texture (sand, clay loam, and clay) and P treatments (P-dipping and two other P fertilizer levels) on growth of NERICA 4 rice in the initial growth stages. In a factorial experiment, we measured the interaction effects of soil texture and P treatments on shoot parameters and root morphology. Both treatments had significant interaction effects on all measured parameters, except shoot biomass, and affected the photosynthetic rate, with the highest mean values obtained under clay loam soil texture and P-dipping treatment, respectively. The treatments also affected rice root morphology. In a striking contrast, whereas mean root length under clay was significantly higher than that under clay loam texture, mean shoot P uptake under clay loam soil was significantly higher than that under clay soil texture. The interactive effect of soil texture and P-dipping influenced NERICA 4 shoot and root physiological and morphological characteristics under clay loam soil texture.