This study was conducted across 24 orchards in the Poro region of Côte d’Ivoire to evaluate the influence of tree age and planting density on cashew tree productivity. Morphological characteristics (height, diameter at breast height (DBH), and canopy spread) and cashew nut weight were measured every two days for 162 trees. To examine the relationship between morphology, planting density, and yield, we employed a one-way analysis of variance (ANOVA) and multiple linear regression analysis using the Ordinary Least Squares (OLS) method. The ANOVA results revealed that planting density is a determining factor for yield. High-density plantations (300 trees/ha) promote vertical growth and increase initial yields in young trees. However, this high density limits long-term DBH and canopy development due to increased competition for resources. Conversely, low-density plantations (75 trees/ha) allow for superior development of these morphological traits, resulting in higher productivity in mature trees. Furthermore, the regression analysis confirmed that DBH (p = 0.017) and canopy spread (p ≈ 0.084) are the morphological factors most significantly influencing yield, demonstrating a positive and significant effect. Our findings demonstrate that adequate spacing is essential to maximize long-term yield and ensure the sustainability of cashew plantations. Individual tree productivity is primarily determined by lateral development (DBH and canopy) rather than vertical growth.