Native to the US and Southern Canada and found coast to coast, Heuchera (HEW-ker-a or HOY-kher-uh) and its hybrid, x Heucherella consist of at least 30 known species.
Precisely how many species are natural or hybrids (Heuchera and Tiarella)has been a subject of much debate.
The genus usually goes by the common names of alum root and coral bells. X Heucherella is commonly known as foamy bells, as the other parent plant is Tiarella (AKA foam flower).
Heuchera hails from the Saxifragaceae family and may be found in both woodlands and mountainous terrain. These hardy perennials are incredibly easy to grow and have a long list of cultivars as a result.
Literally dozens of cultivars exist of Heuchera, most of which are patented. The popularity of these cultivars varies, based on the regions they’re best adapted to.
Two of the most popular Heucherella varieties are “Alabama Sunrise” and “Sweet Tea”.
Size & Growth
This herbaceous shade plant has a central caudex crown that rests on or just below the ground.
Leaves grow from the crown in a clumped spiral. Nodes include a bud which either develops into a new leaf or inflorescence.
Non-hybrid Heuchera has green leaves which change to purple or bronze in winter. This may be accompanied by contrasting maroon or purple veins with white or silver patches.
Hybrids have a much wider range which may include orange, pink, red, or yellow. Heucherella’s leaves are finer and heavily veined.
Heucherella cultivars vary greatly in height, ranging from 4″ to 24” inches. They produce stalks of bell-shaped pink or white flowers in early summer.
Flowering and Fragrance
Beginning in late spring to early summer, Heuchera produces an inflorescence of tiny, bell-shaped florets. By late summer, the floral show is coming to an end, although the display may be extended through deadheading.
Each flower stalk reaches 2 to 3 times the height of the crown and may contain as many as 30 branches. About a dozen florets appear on each branch and may include a range of colors, such as coral, crimson, red, white, greenish white or pink flowers.
The name “coral bells” is in reference to the flowers of a particular species, Heuchera sanguinea.
Light & Temperature
Most Heuchera cultivars love full shade but can tolerate part shade. A few northern varieties are able to handle part or full sun for short periods if the soil’s kept moist.
Heuchera can handle a wide range of USDA hardiness zones 4 to 8.
Eastern species have a higher tolerance to both heat and humidity. Be sure to check the individual tolerances before choosing a specific cultivar. X heucherella is less tolerant to extreme temperatures.
Watering and Feeding
You can add up to an inch of water weekly during the growing season, although both Heuchera and the x heuterella plant are drought resistant and can survive a little neglect. Be sure to reduce watering during the winter to avoid root rot.
More northern gardeners may find adding a bit of mulch by first frost will help protect Heuchera from cold damage.
Soil & Transplanting
Heuchera prefers a rich, moist, well drained soil with plenty of compost or organic matter. Mulch is an excellent way to not only provide protection, but also helps prevent the soil from drying out as quickly. Aim for neutral to slightly acidic pH levels, but be wary of highly acidic soil.
A good potting mix works well for container plants, which will require very little fertilizer.
Grooming And Maintenance
The crown becomes increasingly woody over time, leading to a relatively short lifespan. However, dividing the plant every 3 to 4 years extends this lifespan.
Cut back or deadhead the inflorescence will increase their total bloom time.
How To Propagate Alum Root
Before propagating this plant, make sure the cultivar you have isn’t patented. While it’s okay to propagate through seeds, division and cutting methods are illegal on patented plants.
To propagate by seed, you will need at least two species or cultivars, as Heuchera tends to be self-sterile. Seeds are ready to harvest and sow six weeks after pollination.
You will know which are ready by the brown and split seed pods. It will take approximately 30 days to germinate, and may be potted as early as fall.
For those plants where division is legal, you will want to dig up the clumps every three years and pull the rooted offsets apart. These may be planted directly, or smaller offsets may be temporarily potted.
Offsets which have not suffered desiccation during rooting may be treated as cuttings and do not require root hormone.
Heucherella Pest or Diseases
Heuchea is both rabbit and deer resistant. It is also drought tolerant.
There are few pest problems with the Heuchera or heucherella plant. Black vine weevils can bore into the crown, killing the plant.
These are easily treated with systemic insecticides or introducing natural predators. Foliar nematodes can leave discolored patches in the foliage and cannot be treated.
Sclerotinia is a fungus that’s known to affect some cultivars in hot, humid weather. As with many plants, overwatering increases the risk of root rot.
Suggested Heuchera Uses
Heuchera is one of the most versatile groundcovers, providing vibrant foliage color even when not in bloom. Much like hosta, the plant makes an excellent addition to partial shade areas.
You can substitute Heuchera for Hosta in deer-heavy areas, as the astringent taste of the leaves protects the plant from munching. They fit naturally in rock gardens.
These plants are also an excellent addition to mixed containers where the foliage easily compliments other plants. They attract butterflies and hummingbirds, making them a great choice for gardens overlooked by windows or near patios.
Traditionally, Heuchera roots have been used as a substitute for alum in pickling, leading to one of their common names. The roots are rich in tannin.
Additionally, its properties help shrink tissue, leading it to be a popular home treatment for nose bleed, piles, sore throat, and ulcers.