Periwinkle

Periwinkle is one of those ubiquitous perennials and annuals found in pretty much every garden center in the state of Florida. They are pretty, bloom often and tend to be inexpensive which are all traits that have led to the popularity of this species. Here is some information you don’t find on their plant tag in the garden center.

The Madagascar Periwinkle (Catharanthus roseus) is a commonly cultivated garden perennial. This species has lovely five-petal flowers that range in color from white to deep pink and often have a darker colored center. Madagascar Periwinkles reseed quite readily and have become naturalized or invasive throughout portions of the tropics. Interestingly, the Madagascar Periwinkle is an endangered plant in its native home, a victim of slash and burn land clearing techniques. This species is also used as a nectar plant by various Florida butterflies.

Madagascar Periwinkle contains the alkaloids vincristine and vinblastine which are used as part of treatments for treatment for leukaemia and lymphoma. Vincristine is a mitotic inhibitor and works to slow to production of rapidly diving cells during mitosis in metaphase. Vinblastine decreases the number of white blood cells and is used in treating cancers of white blood cells such as lymphoma. In traditional Chinese medicine, extracts from this plant have been used to treat Hodgkin's lymphoma, malaria and diabetes.

Caution: This species is toxic if ingested by humans or animals and should be avoided in the garden if your children or animals are prone to tasting foliage for fun.

The common name Periwinkle refers to a number of flowering plants of the genus Vinca and the genus Catharanthus. Both genera are members of the Apocynaceae or dogbane family. The genus name Vinca derives from the Latin word vincire “to bind or fetter” and contains six species found in Europe, southwest Asia and northwest Africa. The genus Catharanthus derives from the Greek root words cathar “pure” and anthus “flower”. This genera contains eight species, seven of which are found only on the island of Madagascar with the eighth occurring in India.