The implementation of sustainable building materials is currently one of the principal global challenges faced by the construction industry. Natural bamboo culms are a potential alternative to tackle this challenge due to its favourable environmental credentials as well as affordability. However, the organic geometry of bamboo culms is one of the barriers that prevents them from being implemented in formal design procedures. This work presents the details of a new digitisation workflow to systematically capture the geometry of bamboo culms through the application of 3D scanning technologies and reverse engineering principles. This workflow is applied to carry out a comprehensive analysis of the geometric variability of Guadua angustifolia kunth (Guadua), Phillostachys pubescens (Moso) and Bambusa oldhamii (Oldhamii) to identify potential correlation patterns. This geometric analysis showed a wide variation in the geometric properties of all species and no particular pattern was found which could be adopted for a potential visual grading system. These results highlight the challenges that the use of bamboo culms pose for the traditional design and fabrication processes developed for manufactured structural elements. The proposed reverse engineering methodology adopted for this study can be used to quantify and manage the geometric variability of bamboo culms to support the development of new formal design and fabrication processes for this natural structural element