The Smoke Bush, or Cotinus coggygria, is a deciduous plant prized for its highly decorative and dynamic characteristics throughout the growing season. Known commonly as the Smoke Tree, this species is an ornamental plant with an appearance that changes dramatically. The plant’s distinct look is a combination of its large, colorful foliage and the unique, ethereal structures that give it its smoky moniker. It is a striking specimen that provides both structural interest and movement in a landscape.
Size and Shape of the Woody Shrub
The Smoke Bush is generally a multi-stemmed, upright, and loose-spreading shrub, though it can be trained into a small, low-branching tree form. Its typical mature size ranges from 10 to 15 feet tall with a similar spread, creating a rounded or open, irregular canopy. The bark is initially smooth, often purple or brown on younger stems, gradually becoming rougher and light gray as it matures. The foliage during the primary growing season consists of broadly oval or obovate leaves, typically measuring between 1.5 and 3 inches long, which may be deep bluish-green or a rich, dark maroon depending on the variety.
The Unique Appearance of the “Smoke” Plumes
The feature that truly defines the Smoke Bush is the hazy, mist-like effect that appears to float above the foliage in the summer. This “smoke” is not a traditional flower but rather the elongated, feathery structures of the plant’s inflorescence. The plant initially produces numerous tiny, inconspicuous yellow-green flowers on large, branching panicles. After the flowers fade, most abort, and their sterile stalks elongate and develop billowy, fine hairs, creating the fluffy, cloud-like puffs that cover the shrub throughout mid-to-late summer. The plumes display a delicate range of colors, often appearing as yellowish-pink, purplish-pink, or aubergine, depending on the cultivar, mimicking a cloud of soft smoke hovering over the bush.
Autumn Foliage and Seasonal Interest
The Smoke Bush provides a final visual display as the growing season concludes and the leaves transition into their autumnal colors. The foliage shifts from its summer tone to an intense and varied palette, often including vibrant shades of scarlet, brilliant orange, and bright yellow. Cultivars with purple leaves, such as ‘Royal Purple,’ often deepen to a rich reddish-purple or scarlet before dropping for the winter. The intensity of this fall color provides an accent in the landscape before the plant enters dormancy.