Blue vervain has been used for thousands of years and is not limited to North America. Even the Romans used verbena (another common name) to treat a variety of medical conditions, and the flowering herb was also a popular remedy among the Native Americans.
Perhaps the nutrient-poor sandy soil in their bed is the reason that Brazilian Verbena's spread has been modest. My original plants were winter sown. Seed is easy to collect and share. My original plants were winter sown. Seed is easy to collect and share.
V. bonariensis or purpletop vervain, is a wonderfully versatile annual. Unlike the more common verbena, the purpletop vervain is very tall. These plants can get up to three to four feet tall. They make a great show in a garden setting, especially with other prairie type plants and grasses.
Verbena californica is a rare species of verbena known by the common names California vervain and Red Hills vervain. This flower is endemic to Tuolumne County, California, where it is known from ten or eleven occurrences in the Red Hills, a section of the Sierra Nevada foothills near Chinese Camp.
This Verbena comes from South America, and is one of the most reliable types for regions with hot, humid summer. Plants form a bushy mound of dark green leaves, with branching stems that bear clusters of bright purple flowers from summer well into late fall. Attractive to butterflies. Excellent in containers.