Halesia

halesia

( huh - LEE - zee - uh )

At-A-Glance Information

This genus of deciduous trees, commonly called Silverbell or Snowdrop Tree, includes species which need partial shade and regular water to perform well in the landscape. These elegant trees are native to the southeastern United States and produce bell-shaped white flowers in dangling clusters in springtime. Blooms are most profuse in cold-weather areas. Long-lasting fruits appear after flowers fade. Halesia is wonderful in pollinator and woodland gardens, pairing well with other acid-loving plants like Azaleas and Rhododendrons. Take care when planting these trees in the landscape, as some species are fatally poisonous to humans and animals if plant parts are ingested.

Halesia Species and Varietals

The genus Halesia is a member of the plant family Styracaceae and includes 4 to 5 species. Halesia trees grow best in USDA hardiness zones 4-8 or Sunset growing zones 2b-9 and 14-21. To find your zone, click here: Zone Map.

Halesia carolina (Halesia tetraptera) (Snowdrop Tree, Silver Bell, Little Silverbell, Opossom-Wood)
This species quickly reaches 30-40 feet tall with a 20-35 foot spread. Train plants to have a single trunk when young, or they will form a large shrub. Cultivar 'Wedding Bells' reaches about 15 feet tall and wide, and has larger flowers than the species, making it a great accent, specimen or patio tree.

'Arnold Pink'
With light rose to pale pink flowers. 30-40 feet tall.

'Meehanii'
Shrubby selection to 12 feet tall.

'Rosy Ridge'
Popular pink-flowering form. To 20-30 feet tall.

'Wedding Bells'
Large white flowers to 20 feet tall with a rounded habit.

Halesia diptera (Two-Wing Silverbell, American Snowdrop Tree)
These trees can reach up to between 20-35 feet tall and spread just as wide at maturity. They are often seen with multiple trunks. Halesia diptera magniflora has larger and more profuse blooms than the straight species.

Halesia monticola (Mountain Silver Bell)
These large shrubs reach 60-80 feet in height when mature. This is the largest species in the Halesia genus. Flowers are large. These are not easy trees to transplant, but once they have an established root system, they will quickly grow.

Halesia tetraptera (Common Silverbell, Mountain Silverbell, Carolina Silverbell, Snowdrop Tree)
These widely cultivated ornamental trees are native to the southeastern United States, and reach up to 32 feet tall when mature. Flowers are bell-shaped and white, dangling from branches in spring and summertime.

Caring for halesia

Take care when planting these trees in the landscape, as some species are fatally poisonous to humans and animals if plant parts are ingested. These prized trees prefer a spot in the landscape that receives full sun to partial shade. At minimum, they should be receiving between 4 and 6 hours of direct sun each day for optimal flowering and leafout. In hotter climates, these trees (especially when young) may appreciate some reprieve from direct sun in the warmest hours of the day (between 2 and 3 PM); this can help prevent sunburn and leaf scorch. Halesia trees require well-draining, moist soil that is slightly acidic. They prefer a soil pH of between 5.5 and 6.5, but can tolerate neutral soils as well if necessary. They do not like having standing water around their roots, so avoid planting them in a depressed area of the landscape. Ensure that soil has good drainage before planting; otherwise amend with plenty of sand and organic matter before installation. Post-planting, apply a layer of mulch around the base of the tree. Doing so will increase soil moisture retention, suppress weed growth, and regulate soil temperatures. During the first few years, water trees regularly to help them establish a good root system.

Fertilize yearly in early springtime with an application of 2 inches of compost around the base of plants. Pull mulch back before applying, work the compost gently into the soil a bit, water it in, and then replace mulch. Minimal pruning is needed for Halesia trees; they typically have a natural graceful form. In early spring, simply remove dead, damaged, diseased, or crossing branches. Trees should be shaped when they are young, not when they are mature. As they grow, make sure to thin out the canopy every few years to increase air circulation. These are long-lived perennial trees, able to survive for over 100 years before needing to be replaced in the landscape. They grow at a slow to moderate growth, reaching their mature size in 10 to 15 years.

Propagation

Halesia can be propagated either by using cuttings or from seed. To ensure that your propagated plant will have the exact same qualities and characteristics as the parent plant, use the cutting method. If you would like to experiment and see what plant you can grow from seed, just keep in mind that it will not necessarily be the same as the parent plant. To propagate your tree, follow the instructions below:

Propagating Halesia by Cutting

Gather your materials. You'll need a clean, sanitized, sharp pair of garden shears, rooting hormone, a pencil, and a 3-inch pot filled with well-draining compost or other organic material. A good substrate for propagation of cuttings is a light blend of 1/3 pasteurized soil or compost, 1/3 sand, vermiculite or perlite, and 1/3 coconut coir or peat moss.
In summertime, choose the plant that you'd like to propagate. Ensure that this plant has had a good watering the night before, as this will improve the chances your cutting will take root. Cut one or more 6 inch softwood portion(s) of the end of a non-blooming branch and strip the leaves off of the lower half. Make a hole in your planting medium by pushing your pencil into the soil. Dip the end of the stem in rooting hormone, and plant it in your pot. Fill in soil around the cutting to support it, but do not pack it down too much.
Moisten with water, and ensure that the pot has good drainage. Your pot should be kept in warm, sunny conditions indoors (and not in direct sunlight). Water whenever your soil is dry under the top layer. After about four to six weeks have passed, your cutting should be rooted. When you notice new growth, you'll know you have roots.
Keep your new plant in an area with bright light (though not direct sunlight) and temperatures between 55 and 70 degrees Fahrenheit. Ensure that the soil stays moist, but not wet, until the next spring, when you can transplant it to its new home. Ensure that the last frost of the year has occurred before doing this, as it can seriously damage your new shrub.

Propagating Halesia by Seed

Keep in mind that the plant you get from seed will not necessarily mimic all of the characteristics of the parent plant. To propagate by seed, you will need a paper bag, a pot or tray filled with well-draining compost or other organic material, a spray bottle and a fork. The best potting medium for seed germination is a light blend of 1/3 pasteurized soil or compost, 1/3 sand, vermiculite or perlite, and 1/3 coconut coir or peat moss.
Harvest your seeds. The seed pods on Halesia trees and shrubs are pretty easy to spot; they're large and dangle from the branches, left behind after flowers have faded. Once they have dried out and begun to split open, you can harvest the seeds inside. Cut them off of the plant, placing them in a paper bag. Harvest as many as you can, and place the paper bag in a dry, cool, dark area. They will begin to split open and release the seeds contained inside. Once they have been released, take them out of the bag and put them in a container so you can work with them.
Halesia seeds have a hard coating that protects them, but this coating also makes it a little difficult to get them to germinate. We can help the process along by soaking the seeds in sulfuric acid for 8 hours. The more seeds you treat, the more chances you will have to get the resulting shrub or tree with traits you desire. Next, place your seeds in lukewarm water for 24 hours. Viable seeds will sink to the bottom, and non-viable seeds will float to the top. You can discard any seeds that float.
Place treated seeds in a plastic bag or other sealable container filled with moistened sphagnum moss or sand. Put seeds in the substrate, and place the sealed container in the refrigerator for two months. Halesia seeds are sometimes difficult to get to germinate, and a few rounds of cold stratification may be required with two months at room temperature climate in the middle.
Water your prepared seed tray or pot filled with soil, and ensure that good drainage is occurring. Place your seeds in your prepared pot or seed tray about a quarter inch to a half-inch under the soil surface. Cover them with soil and water with your spray bottle. Place your tray of seeds in a warm area that receives bright, indirect light. A greenhouse is the most ideal climate, but a planting tray inside a window will do as well. Germination usually takes 7-14 days from sowing. Once you begin to see seedlings sprout and they are able to be handled, transplant them to their own individual 3-inch pots, filled with the same potting medium as described in Step 1. Loosen the seedlings from the potting medium by digging down with the tines of your fork about an inch and a half, gently working the seedling up until it is out. Then, replant the seedling in its individual pot.
Keep the seedling's potting medium moist, but not wet, by spraying the soil with your spray bottle. Keep your new plant in an area with bright light (though not direct sunlight) and temperatures between 55 and 70 degrees Fahrenheit. Ensure that the soil stays moist, but not wet, until the next spring (after the danger of frost has passed), when you can transplant it to its new home

Halesia seed pods form on branches after flowers have faded.

Halesia sedds are wrinkled and dark brown to reddish-brown. There are about four seeds per pod.

Problems and Pests

Halesia plants typically have very few pests and disease issues, though they can be susceptible to certain problems depending on the species and growing conditions, including: