Abstract text: Understanding plant growth is crucial to predict crop yield evolution, a major challenge today. Plant growth and morphogenesis is closely linked to the expansion of the cell wall and a key question is how can the cell wall expand without succumbing to the stress imposed by the turgor pressure. Several molecular mechanisms have been proposed. Currently, the "Biomechanical Hotspot" model [Cosgrove, 2016] is the most accepted, coexisting with other emerging models such as "Expanding Beam" [Haas et al., 2020] or "Ca-Pectate Exchange" models [Boyer, 2016]. I will present advancements in a numerical model for growth and morphogenesis based on cell wall mechanical and biochemical characteristics utilizing a nonlinear 3D finite element method. The cell wall is defined as an isotropic nearly incompressible hyperelastic material. To model its expansion, multiplicative decomposition of the deformation gradient is used and adapted in a mixed formalism. The mechanical formalism is carefully addressed to account for residual stresses over the whole process. Special attention is also given to technical aspects such as model reliability or boundary conditions. Through this model, we aim to explore the integration of various non-mutually exclusive growth mechanism to simulate and potentially predict cell wall expansion.