This article reports on an ethnopharmaceutical field study carried out among Turkish migrants in Cologne, western Germany, which recorded 79 botanical taxa and 115 plant-based preparations, encompassing 167 folk phytotherapeutical uses, as well as a few other biological (animal and mineral derived) remedies. One-fourth of the recorded remedies were represented by food-medicines. Half of the ingredients quoted came originally from Turkey; only a few plants were gathered from the wild or cultivated in the Cologne area. This article discusses the Turkish migrants' frequent use of aerial parts of Sideritis species, the fruits of Pistacia terebinthus and the seeds of Peganum harmala from the perspective of modern phytopharmacology, phytotherapy and toxicology. It considers cultural adaptation related to the use of folk pharmaceuticals by analysing the ingredients of the Turkish folk pharmacopoeia and comparing them with those of the Turkish medical ethnobotany and of the phytotherapy of the host country (Germany). Only one third of the remedies mentioned by Turkish migrants living in Cologne are also known in German evidence-based phytotherapy, and less than 10% of the recorded phytotherapeutic uses are common to both pharmacopoeias. This article concludes by suggesting hypotheses on future changes affecting the knowledge and use of medicinal plants within the Turkish community of Cologne. (C) 2005 Elsevier Ireland Ltd. All rights reserved.