Flowering dogwood is a small deciduous tree growing to 10 m high, often wider than it is tall when mature, with a trunk diameter of up to 30 cm. A 10-year-old tree will stand about 5 m tall. The leaves are opposite, simple, ovate, 6 to 13 cm long and 4 to 6 cm broad, with an apparently entire margin (actually very finely toothed, under a lens); they turn a rich red-brown in fall. The flowers are individually small and inconspicuous, with four greenish-yellow bracts 4 mm long. Around 20 flowers are produced in a dense, rounded, umbel-shaped inflorescence, or flower-head, 1 to 2 cm in diameter. The flower-head is surrounded by four conspicuous large white, pink or red "petals" (actually bracts), each bract 3 cm long and 2.5 cm broad, rounded, and often with a distinct notch at the apex. The flowers are bisexual. While most of the wild trees have white bracts, some selected cultivars of this tree also have pink bracts, some even almost a true red. They typically flower in early April in the southern part of their range, to late April or early May in northern and high altitude areas. The similar Kousa dogwood (Cornus kousa), native to Asia, flowers about a month later. The fruit is a cluster of two to ten separate drupes, (fused in Cornus kousa), each 10 to 15 mm long and about 8 mm wide, which ripen in the late summer and the early fall to a bright red, or occasionally yellow with a rosy blush. They are an important food source for dozens of species of birds, which then distribute the seeds.
The tree is commonly planted as an ornamental in residential and public areas because of its showy bracts and interesting bark structure. although it is native to the area.