Verbena Stricta  Also simply called Hoary Verbena, this Vervain has a long bloom time; the blue-purple flower spikes will persist for 4-6 weeks, usually spanning July and August. s an evergreen perennial that is native to South America but has naturalized in the United States from North Carolina to Florida and west to Texas. It has prolific lavender flowers that are known to attract Swallowtail butterflies - bold summer blooms that thrive in bright, sunny areas. The seeds are a staple for many small mammals and birds that depend on this widely-distributed plant.  The gray-green leaves are fuzzy on both sides and are the larval host for butterflies.

The plant is a tender perennial and is hardy from zones 3-8. Grow Verbena bonariensis in moist but well-drained soil in full sun. Given the right conditions, plants will self-seed freely, but in colder regions they may need protection from frost. 

The 1-6 ft., hairy stem produces a terminal cluster of narrow, flowering spikes. Small lavender to blue flowers appear in a ring halfway down the ascending spike. Each flower is about a 0.25-inch purple tube. The leaves are primarily at the base of the plant and form a mounded rosette of green, lance-shaped leaves with serrated margins. 

Deer & rabbit resistant; not considered toxic to pets.