The leaves and petals of vascular plants have complex forms of high diversity. Their organic geometries showcase elegant surface designs which suggest great form and material integration. Because of this potential distinctive synthesis between geometry and materiality, plant leaves can be a good natural biomimetic model for the design and construction of high performance architectural surface structures. This research investigates leaf geometry and material composition with a focus on growth activities and explores the possibility of generating complex-shaped composite surface structures with high mechanical performance from an emergent process. This research has three stages of study: (1) the first study creates a simplified surface generation model by combining accurate mechanical simulations with abstracted cellular unit development patterns. The model is comprehensively parametrized to achieve a high capacity of generating and outputting shape diversity. (2) the second study explores methods to create different vein morphologies in 3D space, and creates a synchronized composite surface structure generation model by running the surface and vein generation models in parallel with each other. From the composite structure generation model, an emergent form-finding method is derived. (3) the third study explores how to translate the digital models of the composite system into physical structures while maintaining the advantages of a growth-based biomimetic system. It tests different options to design a fabrication process incorporating the advantageous aspects of leaf growth as a structure-building process. This research shows a framework of developmental thinking that can lead to the generation of structures with intrinsic component integration.