(Verbena) SUPERBENA® Dark Blue Verbena has large purple-blue clusters of flowers that bloom all season. SUPERBENA® Dark Blue has a strong trailing habit, and is ideal to use as groundcover in front of your landscape beds. SUPERBENA® Dark Blue grows 6-12 inches tall and can trail up to 48 inches long, perfect for window boxes, hanging baskets and combination containers. SUPERBENA® is a heat and drought tolerant series of verbena that will attract butterflies to your yard. The plants are self-cleaning with no deadheading required, and are extremely mildew resistant. If so desired, you may trim your SUPERBENA® to encourage additional branching and a fuller plant.