Coral bells (Heuchera) is a traditional foliage plant with many newer varieties available. Heuchera plants form round mounds with a woody rootstock or crown at their base. Small bell-shaped flowers on tall stems attract hummingbirds and make nice cut flowers. Their leaves are rounded, lobed, hairy, and evergreen—even when covered in snow. Besides traditional green-leaved coral bells, new varieties of heuchera have leaves in shades of purple, rose, lime green, gold, and variegations in between. Heuchera are native North American plants that are at home in woodlands, rock gardens, containers, and borders. They can also be used as ground covers.
|Common Name||Coral bells, alumroot|
|Plant Type||Evergreen perennial flower|
|Mature Size||12 to 36 inches tall and 12 to 18 inches wide|
|Sun Exposure||Full sun to part shade|
|Soil pH||6.0 to 7.0|
|Bloom Time||Spring, summer|
|Flower Color||Red, white, coral, pink|
|Native Area||North American woodlands|
How to Grow Coral Bells
Coral bells make wonderful edging plants and put on a show when planted in groups. Their foliage color is great for playing up the colors of nearby flowers. Darker purple leaves can make yellow flowers, like coreopsis, glow. Butterscotch-colored leaves can bring out the tones of simple green leaves. Pair coral bells with lacy-leaved plants, like fringed-leaf bleeding heart or thread-leaf coreopsis, to highlight their form.
Cut back the entire flower stalk after flowering to put the plant's energy into growing more leaves. Divide coral bells every three to five years to keep them from dying out in the center. If the leaves get a bit ragged looking, especially after winter, cut them back and new growth should fill in quickly.
The larvae of the black vine weevil can bore into the crowns and roots of coral bells. The larvae are usually present in late summer/early fall. Affected plants will wilt and droop. You should be able to see the larvae and remove them by hand and destroy them.
Coral bells do best in full sun to partial shade, with partial shade preferred in hotter climates. The color can wash out in full sun, and too much heat and light can cause the leaves to scorch. If you grow yours in full sun, give it extra water. Coral bells planted in damp shade can be prone to fungus diseases. If your plants start having problems, it's best to move them to a drier or sunnier site.
Coral bells like a neutral to slightly acidic soil pH, somewhere between 6.0 and 7.0. Good drainage is a must, especially in shaded areas. Sitting in the damp soil will cause the crown to rot.
This plant has medium water needs. It likes consistently moist soil. It will tolerate some weeks without water, but an inch of water per week is best to keep it happy.
Temperature and Humidity
Most coral bells are hardy in USDA hardiness zones 4 through 8, although hardiness does depend on the variety you are growing and how hot or cold it gets. In cold areas, coral bells crowns can heave above the soil line in the winter. Winter mulching after the ground freezes hard will help prevent thawing that pushes the plants up. Check periodically to make sure the roots are not exposed.
Feed coral bells in the spring with a 1/2-inch layer of compost or a light amount of slow-release fertilizer. This plant has light feeding needs; you should avoid heavy applications of quick-release fertilizers, as this will inhibit flowering.
Varieties of Heuchera
- Heuchera 'Autumn Leaves' changes color through the seasons, from red to caramel to ruby.
- Heuchera 'Chocolate Ruffles' has ruffled leaves with rich chocolaty color on the top and deep burgundy on the bottom.
- Heuchera 'Green Spice' has large green leaves veined in maroon and is very hardy.
- Heuchera 'Marmalade' has frilly leaves in shades from umber to deep sienna.
- Heuchera 'Tiramisu' has chartreuse leaves, tinged with red. It changes in color throughout the season.
Growing From Seeds
You can start the species Heuchera from seed, but the hybrids will need to come from plants or divisions if you want plants that look like the parent.
When starting seed, sprinkle the seed on the surface of the soil in late fall or early spring. Don't cover the seed, as they need light to germinate. You can also start the seeds indoors, a couple of months before you plan to transplant. Seeds take two to eight weeks to germinate. Transplant the seedlings outdoors after all danger of frost has passed.
Plant container-grown coral bells any time after frost. Keep them well watered their first year. Other than that, they shouldn't require more than some relief from the extreme heat and rich, well-draining soil.