Verbena bonariensis - Verbenas are long blooming annual or perennial flowers that possess the virtues of heat tolerance and an extremely long bloom season. Verbenas require a location that receives full sun throughout the day. They must have well-drained soil. 

They grow as tall as 3 - 6 feet tall and 1 - 3 feet wide. This light, airy giant provides a soft, flowing backdrop for a layered bed.