Catharanthus roseus Catharanthus roseus – Madagascar Periwinkle Found in Propagation Glasshouse at Chelsea Physic Garden Madagascar Periwinkle is indigenous to Madagascar, but is cultivated and naturalised throughout the tropics and parts of the subtropics. We can only grow this at Chelsea Physic Garden as we are able to take cuttings of the tender plant and grow them on over winter in our Propagation House, before planting them outside after the night temperatures have risen. In traditional medicine, Madagascar Periwinkle has been used to treat a variety of ailments in Madagascar as well as in other parts of the world where the plant has naturalised. While researching the anti-diabetic properties of the plant in the 1950s, scientists discovered the presence of several highly-toxic alkaloids in its tissues. These alkaloids are now used in the treatment of a number of different types of cancer, with one derived compound, called vincristine, credited with raising the survival rate in childhood leukaemia from less than 10% in 1960 to over 90% today. These alkaloids work by disrupting cell division or 'mitosis', stopping the process when newly-copied DNA is split into two identical parts to produce two identical new cells. Powerful medicinal plants such as Madagascar Periwinkle remind us of the need to conserve and study the increasingly threatened plant habitats of the world. In the 1960s, when these alkaloids were discovered, rich Western countries saw little need to reward the original homeland of the periwinkle, Madagascar, for the riches that had been earned from the plant. Today, there are regulations such as The Convention on Biological Diversity that ensure the rewards from discoveries such as these are shared fairly with the country from which they came. Find out more about our Glasshouse Restoration Project.