landscapesilverbells
flowering
Many of us are adding to our landscaping this time of year, making plant choices to increase the beauty of our homes in years to come. Flowering trees are often at the top of the list. Even though their bloom time is past, let us consider two less than usual spring flowering trees that I know you would enjoy in your gardens.
When we think of spring flowering trees, the dogwood (Cornus florida) and the redbud (Cercis canadensis) tend to come to mind first. These are our best known native flowering trees. We love them dearly for their great beauty and, at a deeper level, because they belong here. These trees are part of Kentucky, our home.
Dogwoods typically grow to 15 to 30 feet tall, with a bloom time that overlaps with the redbuds. The true dogwood flowers are actually tiny, yellowish green, button-shaped clusters. What we call the bloom is the four showy, petal-like bracts which open flat and give the appearance of a large flower. In the fall, the leaves turn red. The bright red fruits, poisonous to humans but loved by the birds, mature in the fall.
Unfortunately, especially when stressed, dogwoods can have disease issues. The most serious is dogwood anthracnose, but they are also susceptible to other diseases, and when stressed, they become vulnerable to borers. Water them well during times of drought to avoid stressing them unduly.
Don’t stop planting dogwoods, but in the interests of increasing biodiversity, here are two other lovely spring-flowering trees that you might like to consider adding to your garden. While there are other species of each of these trees, I will stick to those that are most likely to be found at a garden center.
Carolina silverbell (you may see two scientific names for this tree, Halesia carolina or Halesia tetraptera) grows as an understory tree, 30 to 40 feet tall, along streams in the southeastern states. While not native to Kentucky, they will grow here just fine. These trees thrive in the same habitat as our native dogwood, preferring evenly moist, well-drained, slightly acidic soil, in full sun to part shade. While they will not do well in difficult sites, the silverbell should be fine in a normal garden setting. They can be grown with multiple stems or trained as a single-trunk tree.
The silverbell blooms in the spring, just before or just as the leaves start to emerge, with small, bell-shaped, white flowers in drooping clusters. These blooms have a dainty, delicate beauty. Four-winged, brownish fruits appear in the fall. They are quite interesting looking and often persist well into the winter.
Fall color isn’t a big selling point, being a rather muted yellow-green. The bark is lovely, though, a light gray with darker striations.
In the same family as the Carolina silverbell is the Japanese snowbell (Styrax japonicus), which has been called a “tree of singular grace and beauty.” It has the same preferred growing conditions as the silverbell and similar drooping clusters of white, bell-shaped flowers in the spring. These flowers are easily visible because of the upward-growing positioning of the leaves. Flowers give way to greenish olive-shaped fruits in the fall. Again, fall color tends to be insignificant but the gray bark produces fissures that reveal inner orange bark, which can be attractive.
Japanese snowbell is native to China, Japan, Korea and the Philippines. It is a compact, 20 to 30 foot tall tree with horizontal branching, a rounded crown and glossy green leaves.
Both of these trees have no serious insect of disease problems. The silverbell is susceptible to chlorosis in high pH (that is, alkaline) soils. I have seen a number of beautiful specimens in Lexington, none of which appears to be having this issue. The styrax doesn’t tolerate drought well, so watering well during periods of heat and lack of sufficient rainfall will help to avoid stressing the tree. This will be especially important during the first two years after planting to establish a strong root system.
Spring is already a gorgeous season in the Bluegrass. Carolina silverbell and Japanese styrax, with their beautiful blooms and attractive form, are worthy to join in the celebration.