Buttonbush (Cephalanthus occidentalis) is usually found in wet soils, such as swamps or the soil adjacent to the edge of a pond or stream. It grows well in wet soils overhanging water and its branches provide shade for spawning crappie and ducks. It can also grow well on moderately dry soils, as long as it gets enough water when it is becoming established.
Starting in June and continuing through September, you can find 1-inch diameter round, spiky-looking blooms all over this shrub. The flowerheads are composed of multiple tiny white flowers, making it resemble a small round pincushion. It’s a unique bloom and it really stands out in the garden.
In the fall, the leaves turn reddish-brown or yellow in color. This shrub is deciduous, losing its leaves in the winter.
Food and Cover for Birds, Bees, and Mammals
The flowers on a buttonbush tree attract butterflies, moths, bees, and even hummingbirds. These insects and birds feed on the nectar produced by the flowers.
After the cluster of tiny flowers is done blooming, it produces a ball of nutlets in the fall that are fed on by ducks and songbirds. These nutlets start out red in color and then turn brown as they age. Some studies report that over 24 species of birds feed on the seeds produced by buttonbush (Source: The Morton Arboretum).
Deer and a few other mammals will feed on the new growth of the plant, but the plant is known to produce a poisonous substance in its bark and leaves called cephalathin.
When grown near water, buttonbush is often used by wood ducks to rear their brood or as cover. The NRCS reports that the seeds are eaten by 8 species of waterfowl.