by Kyle Sweet, The Sanctuary Golf Club, Florida Master Naturalist
The Periwinkle has quite the claim to fame on Sanibel, as the namesake for what could be called our Main Street and as that hardy small flowering shrub that springs up randomly all around the island adding to our beautiful, lush landscape. Native to Madagascar, India and tropical Asia, Madagascar Periwinkle blooms throughout most of the year in the warm, humid and often dry weather of our barrier islands.
Madagascar Periwinkle, Catharanthus roseus, which was formerly known as Vinca rosea, is also known as Bright eyes, Cape periwinkle and Rose periwinkle, grows to a height of about three feet tall with glossy green leaves and that are three to four inches long. It’s flower exhibit a variety of colors. The center of the 5 – petaled flower is hollow, which differentiates it from a similarly known flower, the flower of the impatiens.
As an ornamental plant, it’s well liked due to its hardiness in dry and low nutrient conditions. If prefers full sun and well drained soils but will handle plenty of morning or afternoon shade and still thrive.
In addition to promoting this plant as low maintenance color in the landscape, the Madagascar Periwinkle has been cultivated for many years as a herbal medicine. In Indian and Asian countries, extracts from both the roots and shoots have been used against diseases such as diabetes, malaria and Hodgkin’s lymphoma. Significant research is underway and ongoing to determine the full medicinal benefits of this plant.
You will find this tough annual flowering plant all throughout the state of Florida as well as in Georgia, the Carolinas, Alabama, Mississippi, Louisiana and Texas. Beyond these Southeastern states, it can be found in Hawaii and California. It’s described as an invasive in Australia, where it has become naturalized, but hasn’t reached that status in the United States, except for in the Florida Keys, where is considered a Category 3 Exotic. Beyond the Keys, it hasn’t been documented to dominate habitats the point of crowding out of other plants.
While enjoying the hundreds of acres at the Sanctuary Golf Club for the past 25 years, I can’t help but continually enjoy the “surprise” of the establishment of this flowering shrub all throughout the property. This low-maintenance, colorful, non-native is a staple on the islands. If you look around, you’ll see that it seems to show up in just the right spot to add to the beauty of the islands.
Does anyone know what has happened to all the morning glories that used to glorify our road sides and generally be all over the island? I haven’t seen any this winter season as I have in years past.