Despite a growing understanding of the importance of knowledge co-production for just and sustainable urban transformations, early career green infrastructure experts typically lack opportunities to practice transdisciplinary knowledge co-production approaches within their normal training and professional development. However, using online collaboration technologies combined with peer- and problem-based learning can help address this gap by putting early-career green infrastructure experts in charge of organizing their own knowledge co-production activities. Using the case study of an online symposia series focused on social-ecological-technological systems approaches to holistic green infrastructure implementation, the authors discuss how critical pedagogical designs help create favourable conditions for transdisciplinary knowledge co-production. This paper suggests that the early career position offers a unique standpoint from which to better understand the limitations of current institutional structures of expertise, with a view towards their transformation through collective action.