Buddleja davidii is a fast-growing, deciduous shrub that typically reaches 6 to 12 feet in height, forming an open, vase-shaped outline with long, arching branches. Its opposite leaves are lanceolate to narrowly ovate, usually 4 to 10 inches long, with sharply pointed tips, serrated margins, and a rough, gray-green upper surface. The underside is densely covered in fine, whitish hairs that give it a silvery cast. Inflorescences appear in terminal and upper axillary panicles, often 6 to 18 inches long, composed of numerous small, tubular flowers with four spreading lobes. Floral colors range from deep violet and lavender to pink and pure white, usually with a contrasting orange throat. The flowers are strongly fragrant and produced from midsummer into early fall. Stems are slender and somewhat brittle, covered with a thin, peeling bark that becomes more fibrous with age. Fruits are small, two-valved capsules containing numerous dustlike seeds. The species favors full sun and well-drained soils and is known for its rapid growth, drought tolerance, and prolific seeding.