This article looks at the development of the regulation of traditional herbal medicines in the European Union (EU) context and its effects in the United Kingdom (UK). Drawing on socio-legal encounters with science and technology studies (STS), it explores how UK and EU stakeholders have struggled to regulate herbal products, and suggests that in order to tackle growing concerns about their safety, emerging EU legislation built on socio-technical imaginaries of ‘tradition’. We argue that in doing so, the law also reshaped herbal medicines in the UK, rewriting their histories and potential futures by fostering new practices of herbal medicine making that sit precariously on the boundaries of what is lawful. Through an empirical exploration of the everyday landscape of herbal medicine in the UK, this article shows how the label of ‘tradition’ embedded in the new legislation transformed and unsettled the existing material practices and relationships that had underpinned herbal and traditional medicine.