Pelargonium cotyledonis
At the Ruth Bancroft Garden, we grow quite a few species of Pelargonium (family Geraniaceae) native to South Africa, where the majority of the species are found. This one is an exception, since it comes from the tiny island of St. Helena in the Atlantic Ocean. It differs from all other Pelargonium species in having symmetrical pure-white flowers, and is classified in a section all to itself. The rough-textured leaves and white flowers are very attractive, as are the thickened succulent stems (see lower photo). The rainfall in St. Helena comes mostly in the winter, and this species goes dormant for a time in the summer.
-Brian