Many plants receive common names that describe their appearance or behavior. The plant known both as the Obedient Plant and False Dragonhead features one of the most descriptive common names in the botanical world. This unique moniker refers to a specific physical characteristic that sets it apart. We will examine the reason behind this unusual trait and explain why gardeners gave this native perennial such a memorable name.
What Exactly Is the Obedient Plant
The Obedient Plant is scientifically classified as Physostegia virginiana, belonging to the mint family, Lamiaceae. This herbaceous perennial is native to various regions across North America, often found in moist meadows and along stream banks. It grows tall, producing spiky stalks covered in showy, tubular flowers, usually pink or lavender. This striking appearance helps it stand out in natural landscapes and garden settings.
The Origin of the Name
The plant’s common name stems from a highly unusual physical property of its individual blossoms when they are on the flower stalk. If a person gently pushes or twists one of the bell-shaped flowers on the spike, it will remain fixed in that new position. Unlike most flowers that spring back toward their original orientation, this species appears to “obey” the placement it is given.
This lack of spring-back is attributed to the specialized structure of the flower’s pedicel, the small stalk connecting the individual flower to the main stem. The joint where the flower meets the stem is stiff and lacks the flexible elasticity found in many other plant species. The rigidity creates a high level of frictional resistance within the tissue.
When the flower is moved, the forces of friction within the stiff joint are strong enough to overcome the restorative forces that would typically pull the flower back to its initial position. This mechanism allows the flower to hold its new angle or rotation until an external force moves it again. The ability to manually manipulate and set the flower’s position is a rare biological trait that directly inspired the “obedient” description.
Cultivating the Plant
Gardeners often appreciate the Obedient Plant for its late summer blooms and its ability to attract pollinators like hummingbirds and bees. When cultivating this perennial, it performs best in full sun to partial shade exposures to encourage robust flowering and strong stem growth. It adapts well to various soil types but prefers consistently moist, well-drained conditions, mirroring its natural habitat alongside streams and meadows.
A significant consideration for home gardeners is the plant’s aggressive growth habit, as it spreads enthusiastically via underground rhizomes. Without proactive management, the plant can quickly colonize large areas of the garden space, potentially overwhelming less vigorous neighboring plants. Pruning the spent flower stalks can help limit self-seeding and manage its spread.