While it is true that the annual Vinca will tolerate most conditions and still look great, this may be a bit much!
I was vacationing in Fire Island a few weeks ago and on an early morning walk I came upon this lovely flower nestled in a cocktail glass. The way the glass was buried deep into the sandy soil made the arrangement seem somewhat deliberate, however, there isn't enough soil in the glass to make me think this was a real container planting. Regardless, I still thought it was fun to see!
The annual Vinca or Madagascar periwinkle (Catharanthus roseus), could be found in many of the gardens on Fire Island. It can be identified by the dark, glossy green leaves and the five petaled flat flowers, usually with a darker "eye." It is heat and drought tolerant and also interesting to note, it is poisonous if ingested or smoked.
There is also some interesting history on this plant. According to the Encyclopedia of Life website, Catharanthus roseus is native to Madagascar and for many years was used as a folk treatment for diabetes. In the 1950's, researchers discovered that the plant contained a group of alkaloids that, although toxic, had potential uses in cancer treatment. Two of these alkaloids, vincristine and vinblastine, can be used in purified form to treat common types of leukemia and lymphoma. The discovery of vincristine is credited with raising the survival rate of childhood leukemia from under 10% to over 90%. Thousands of children's lives have therefore been saved by an extract of this humble garden plant.
Pretty amazing stuff from such a small, unassuming plant!