Flowering Trees and Bushes
Northern Catalpa
Catalpa speciosa
Photo: Illinois Wildflower
Most people think of flowering trees and bushes as a spring event. While there are many that are reliable spring bloomers, including lilac, magnolia, and crabapples, there are some that come later that can enhance the landscape.
On the larger size (over 50 feet), consider Catalpa (Catalpa speciosa). Native to Wisconsin and hardy to zone 4, it has large, fragrant, showy, white flowers through mid-June. The long, interesting seed pods persist through the winter and have entertained many children.
More suited to a smaller landscape it the Japanese Tree Lilac (Syringa reticulata). Not the traditional bush lilac, this is a small tree native to Japan, but it does well in Wisconsin’s northern climate. Among its distinguishing features is a reddish-brown peeling bark, similar to cherry. But the best draw is the twelve inch long, stunning, creamy white, fragrant flowers that bloom in the late spring and into the early summer, later than the typical lilac bush. These flowers will attract multiple pollinators including bees, butterflies, and hummingbirds.
Smokebush or Smoketree (Cotinus spp.) is another choice that will provide interest later in the year. Whether it develops into a bush or a tree will depend on how it is pruned. It can become a small tree if a dominate leader is chose and developed, or remain a bush if allowed to branch. The display is not actually the tiny, insignificant flowers, but the billowy hairs attached to the stems on the spent flower stalks. These hairs will persist through the summer for smokey purplish-pink wonder.
The Seven Sons Flower (Heptacodium miconioides) is another large shrub/small tree. It is only hardy to zone 5, and since it will tolerate partial shade, it might be wise to give it a somewhat sheltered location. It produces fragrant, creamy white flowers in late summer. After the petals fall, the pink sepals remain giving the appearance that the plant is flowering again.
The little-known and underused Amur maackia is a compact rounded tree perfect for smaller landscapes. Native to a region of the Amur River which serves as a border between Siberia and China, it got its name from the Siberian explorer Karlovich Maack. It is a slow growing but aesthetically appealing tree. A member of the pea family, it has flat, brown, 2-3 inch pods that occur after the flowers bloom. The snowy white flowers do not appear until mid-July, making it one of the latest blooming specimens available.
Regardless of the choice of trees or bushes, be sure to choose the location carefully. New trees come from the nursery as skinny little things. They will not remain as such and need to have plenty of space to grow. Be sure to research carefully the mature size and place them in the landscape accordingly, an appropriate distance from any home, structure, or street.
Take into consideration light requirements, soil conditions, and drainage. It is always wise to do a soil test before planting a high value item like a tree. By putting in the time to adequately consider the best conditions for the new purchase, the best results are sure to follow.
Flowering trees and bushes are not just for the spring; nor are blooms just for perennials and flowers. Branch out and consider one of these fascinating and beautiful trees to improve the landscape.
Carol Shirk
Certified Master Gardener