Verbascum thapsus is among the most recognizable roadside plants in North America, though it is a European and Asian native that has thoroughly naturalized coast to coast. In its first year, it builds a flat rosette of large, densely felted silver-green leaves that remain evergreen through winter, looking strikingly similar to lamb's ear at ground level. In year two, a single stout flower spike rises rapidly to 6 or even 10 feet, densely packed with fragrant yellow flowers that open progressively upward through the season.

The plant dies completely after flowering, but volunteer seedlings perpetuate it year after year in any spot with full sun and sharp drainage. Sandy, rocky, or otherwise poor soils suit it best; lean conditions keep the flower stalk compact enough to stand without staking. Common Mullein tolerates drought once established and shrugs off deer and rabbit browsing. It is listed as noxious in Colorado and Hawaii, so gardeners in those states should consult local guidance before introducing it. Where it is welcome, the spent flower stalks, cut to 12 to 24 inches and left standing, provide nesting habitat for cavity-nesting native bees.