Carolina silverbell is a deciduous tree or large shrub that bears white bell-shaped flowers in early spring. The plant naturally forms multiple stems and can be grown that way as a large shrub or it can be trained into a single-trunk tree by removing all but one central leader trunk. It's a good choice for woodland borders or as a specimen lawn tree—rhododendron shrubs are often planted happily beneath its canopy. Best planted in the spring, this plant grows at a medium rate, eventually forming ovate-shaped green leaves that are two to five inches in size. The plant's bell-shaped flowers hang in clusters; the fruits are drupes with four wings, starting out green but changing to white and eventually a papery brown as they mature and dry out.
|Botanical Name||Halesia carolina|
|Common Names||Carolina silverbell, silverbell tree, mountain silverbell, snowdrop-tree|
|Plant Type||Tree or multi-stemmed shrub|
|Plant Size||30–40 feet tall, 20-35 feet wide|
|Sun Exposure||Full sun to partial shade|
|Soil Type||Moist but well-drained|
|Hardiness Zone||4 through 8 (USDA)|
|Native Area||North America|
Carolina Silverbell Care
Behind its delicate appearance, Carolina silverbell is actually a fairly hardy, easy-to-grow spring plant that bridges the gap between a shrub and a tree and is appealing both when flowering and throughout the rest of the season. It's usually planted from container-grown specimens (found at a nursery or garden center), as seeds take a long time to germinate.
When it comes to caring for the Carolina silverbell, it has few requirements beyond a slightly acidic soil pH level; master that (and provide it with enough light) and you're almost guaranteed to have a happy plant that will enliven your landscape for years to come. Additionally, the plant has no serious pest or disease issues.
Carolina silverbell plants grow best in a partially sunny spot, though they can also tolerate full sunlight. Your best bet is to find a place in your landscape that receives full sun in the morning but partial shade in the hotter afternoon hours so that the plant can soak in the necessary sunlight (about six hours daily is best) without burning.
Carolina silverbell plants prefer medium-moisture, well-drained soil that is somewhat acidic—it grows well in conditions similar to those that azaleas and rhododendrons love. If the soil in your landscape is not acidic enough (a pH level around 6.5 is best), you can amend the soil to create the proper environment.
To keep your Carolina silverbell happy, maintain consistently moist soil conditions. If you live in a particularly dry environment, it might be wise to set up an irrigation system, especially when the tree is young. Once established, your Carolina silverbell will be moderately tolerant of drought.
Temperature and Humidity
Carolina silverbell's native habitat is the moist, protected forests of the lower Appalachian Mountains, so it will do best in an environment that mimics those conditions. Extreme heat and dryness stress the plant, especially when it is young.
Feed your Carolina silverbell with an organic fertilizer at planting time and then again each spring until the tree is fully established. When the plant is established, supplemental feeding is not necessary.
Types of Carolina Silverbell
There are several different varieties of Carolina silverbells, with most differences being in the color of the flowers. For pink flowers, plant ‘Rosy Ridge’, 'Rosa', or ‘Arnold Pink’—if you like variegated leaves, look for ‘Silver Splash’ or 'Variegata'.
This plant may form multiple trunks, so choosing one as a central leader when it is in its early years and pruning away the lower branches can help give this a tree form. As with any tree or shrub, damaged or diseased branches should also be removed periodically.
Propagating Carolina Silverbell
You can propagate new Carolina silverbell plants by taking softwood cuttings, with the best time to do so being early June. Treat branch cuttings with a rooting hormone, then plan them cutting-side down in pots of growing medium. Enclose them using a plastic bag to increase humidity. Cuttings can normally be planted in the landscape the following spring.
How to Grow Caroline Silverbell From Seed
If you are trying to germinate seeds, store them first for two to three months in warm, moist conditions between 70- and 80-degrees Fahrenheit, followed by a similar period of cold stratification at 34 to 41 degrees Fahrenheit. Even with this treatment, the seeds may have difficulty germinating—some gardeners report that the process can take up to two years.
When planted in the proper USDA hardiness zones, Carolina silverbell doesn't need any particular winter protection. For young trees, several inches of mulch over the growing roots can provide peace of mind.
Common Pests and Plant Diseases
Carolina silverbell is quite resistant to pests. It can develop scale if the tree is stressed, dealing with drought, or the soil pH is too alkaline.
Common Problems With Carolina Silverbell
The only puzzling problem some gardeners might have with Carolina silverbell is a yellowing of the leaves. This can usually be attributed to chlorosis, which occurs as a result of growing in soil that is too alkaline (soil pH is too high). Amending the soil to make it more acidic will be necessary to help ensure the best health of your Carolina silverbell.
How long does Carolina silverbell live?
With the proper care and conditions, this tree can live for 100 years or more.
What trees are similar to Carolina silverbell?
Mountain silverbell looks very much like Carolina silverbell but tends to be much bigger, growing up to a height of 80 feet. It also has a conical habit, rather than the delicate spreading of the Carolina variety.
How fast does Carolina silverbell grow?
Given optimum conditions, your tree might grow up to 15 inches each year, perhaps a bit more.