Plant biodiversity DNA banks are scarce despite the current plant biodiversity loss, their value for ex situ conservation, DNA preservation progress and the rapid growth of DNA-dependent research fields. We explore the principles and basic organization of plant biodiversity DNA banking and propose new ways of addressing the biodiversity loss through their implementation. Small Department collections could be created through a 6-step holistic process aiming to interconnect 3 types of collections (DNA extracts, DNA-rich tissues and herbarium vouchers) while generating Extended Specimens that would contribute to local and global plant biodiversity knowledge and conservation efforts. We propose a change in the international biobanking strategy (the 2 Dynamo scheme) as interconnecting many small Department collections would put fewer samples at risk in case of catastrophe, optimise sampling strategies and cover in depth more taxa and distribution ranges, while encouraging national and international collaborations.