ReRoot is a biodesign experiment that investigates how plant roots can become both material and collaborator in the design process. The project draws on the behavior of roots in response to environmental stimuli, using digitally fabricated templates to guide root growth into controlled patterns. Inspired by natural precedents such as the living root bridges of Meghalaya and the work of artists like Diana Scherer, the project merges botanical intelligence with architectural intent. Through a series of iterative experiments using cress and wheatgrass, the team explores how roots can form textile-like or spatial structures—gluing, twisting, and adapting to meshes, foams, and 3D printed scaffolds. ReRoot challenges conventional fabrication logics by positioning plants not as static materials, but as active agents of construction, opening new horizons for circular design, slow fabrication, and multispecies collaboration.