Verbena hastata Hardy North American perennial wildflower. Beautiful spikes of purple blossoms, summer into fall. Vervain is a prolific self-seeder; cut back plants before they go to seed if you don’t want this to become an issue. Attracts many pollinators. Full sun to part shade. Stratify seed. Leaf used as tea or tincture. Sowing depth: For tiny seed cover very lightly, otherwise sow no deeper than 2-4 times the seed diameter.