Grow Heuchera ‘Coral Bells’ For Pronounced Foliage That Changes Colour With The Seasons
Reviewed By PETER LICKORISH
Peter is a Horticulture Lecturer and self-employed Horticulturist, with a passion for diverse areas of the industry - from garden design to the science behind plant growth and propagation. He has completed the Royal Horticultural Society’s Master of Horticulture (MHort) Award and lectures on RHS courses at Bedford College.
IN THIS GUIDE
Heuchera plays the lead role in the Drama of Foliage enacted in your garden – and there’s no ‘off-season’ – for this drama plays year-round.
To begin with, this plant has appealing leaf shapes, being attractively lobed or scalloped.
It presents hues in numerous tones and varying intensities, and exhibits prominent veining and marbling.
On top of this, it even undergoes colour changes with the seasons!
They are low-care to no-care bushy evergreen perennials with a mounding or clumping form.
Overview
| Botanical Name | Heuchera |
| Common Name(s) | Coral Bells |
| Plant Type | Perennial Flower |
| Native Area | North America |
| Hardiness Rating | H6 |
| Foliage | Mostly evergreen |
| Flowers | Grown more for foliage, small tubular flowers, sometimes with colourful calyxes |
| When To Sow | March, April, September, October |
| Flowering Months | June, July, August |
| When To Prune | March, April |
Sunlight
Preferred
Full Sun
Exposure
Sheltered
Size
Height
0.1 – 0.5M
Spread
0.5 – 1M
Bloom Time
June – August
Soil
Preferred
Most Soil Types
Moisture
Moist but well drained
pH
Neutral / Alkaline
Many or even most species provide year-round splashes of colour – red, wine, purple, orange, lime, copper, silver, gold…and that’s just the foliage!
On top of this, many varieties’ leaves change colour from one season to another, often dramatically.
Variegation? But of course. And there’s a bonus: most varieties bear thyrses of tiny flowers in summer; sometimes their colour matches that of the foliage and sometimes they provide an accent or complement.
And that, in a nutshell, is Heuchera.
It is hardly any wonder that these eye-pulling plants have exploded in popularity over the past 20 years, with a concomitant explosion in the number of varieties.
While Heuchera has more than 50 species (not including synonyms), hybrids and cultivars number several hundred and counting.1Heuchera (Alumroot, Coral Bells, Heuchera). (n.d.). North Carolina Extension Gardener Plant Toolbox. Retrieved March 17, 2023, from https://plants.ces.ncsu.edu/plants/heuchera/
The Heuchera spectacle has a ‘feature attraction’ plus a ‘sideshow’ – the latter being the small flowers which set themselves well above the foliage, rising to twice to thrice the height of the canopy.
As such, they are effectively a second tier of ornamentation.
Each peduncle has multiple branches and each of these bears a panicle – technically a thyrse – of florets.
These dainty things are very colourful in their own right, coming in white, cream, pink, and various shades of red.
And they attract equally colourful butterflies and also bees.
Heuchera as a genus is also informally called Coral Bells and Alum Root though this is not strictly correct as these vernacular names refer, or used to refer, to different sets of species within Genus Heuchera.
Last but most importantly, in winter, when all else is dead or dormant, Heucheras in the garden can be a blessing, bearing proof of life and also displaying colours soothing to thrilling, and of every mood in between.
Heucheras are native to and grow throughout North America.2Winter, N. (2017, January 12). Heuchera are native to the U.S. and an award-winning perennial plant. CAES Newswire. Retrieved March 17, 2023, from https://newswire.caes.uga.edu/story/6065/coral-bells.html
Moreover, their various species sprout in all kinds of habitat.
Though a particular diversity of species occurs in montane regions, they are also found on river banks, littoral zones, forested regions, and even rock and crag.
Habitat & Growing Conditions
Genus Heuchera includes many strong and tough species that grow in many locales and conditions that are inhospitable for most plant life, such as rocky fissures, barren slopes, and canyon floors.
Other species grow in more hospitable locations, such as wooded hillsides and grasslands.
Furthermore, as they grow through nearly the breadth of North America and throughout its length from Northern Canada to Southern Mexico, different species are acclimated to very different temperature, humidity, and rainfall conditions.
As a result, different varieties have different preferences and tolerances depending on which species they were hybridised or cultivated from.
In general, H. villosa cultivars are hardier at both temperature extremes than H. micrantha cultivars.
That said, as British weather does not get very hot – at least not the way it does in, say, the South of Spain – the chances that a Heuchera species or variety will be affected by heat are slim.
Most varieties are H6 hardy – making them suitable for almost all outdoor areas of the UK.
How To Grow Heuchera
Heuchera can be planted or transplanted in spring or autumn.
In general, Heuchera are as if tailor-made for borders, accents, and rock gardens.
It is true that these plants provide superlative backdrops or foregrounds to set off tall, stately plants, for example a specimen delphinium.
However, they are ornamental plants in their own right, and different varieties can be used for different functions in different settings.
They can be presented in wide planters, used as touches of colour in the corners of a deck, used for year-round decoration on the balcony – the possibilities are limited only by a gardener’s imagination.
Plant Care
Some Heuchera, such as H. ‘Bella Notte’, prefer full sun or partial sun, others, such as H. ‘Citronelle’ are happier with partial shade or full shade, and yet others, such as H. ‘Green Spice’ couldn’t care less.
The key indicator is the colour and shade of the foliage.
The more purple or more red the colour and the darker its shade, the more sun the plant should get; the more yellow-green the colour and the lighter its shade, the more shade the plant should get.
They should be grown in a light, loose, sandy loam. They should not be planted in heavy or clay soils.
Heuchera do not need much care; all you need to do is watch out for a couple of “Dont’s”.
Moist but well-drained soil works best for these plants from spring through autumn when they should be watered in the morning once or twice a week during dry spells.
However, in winter be sure that the soil stays dry, and water it infrequently.
Feed Heuchera lightly and sparingly, if at all. Do so with organic compost or with a 5-5-5 fertiliser.
“Though I am generally not too fussy about clearing up fallen leaves in beds and borders, it is well worth taking the time to clear up any leaf fall around Heucheras,” says Peter Lickorish, Master Horticulturist.
“Leaf litter can make them prone to rot or cause their growth to become distorted if it is deep.”
Common Diseases & Problems
In the main this plant is resistant to pests and diseases, except for two problems that do tend to affect it: vine weevil and a fungus now known as Heuchera Rust.
Vine Weevils
Though adult vine weevils are bad, the grubs are worse because they destroy the plant’s roots.
Small animal life commonly inhabiting gardens prey upon vine weevils so these are your first line of defence.
A biological solution is to release beneficial nematodes that kill vine weevils, such Nemasys Vine Weevil Killer.
A third, chemical, option is to use biological insecticides, though this may also harm other beneficial wildlife in your garden.
Look out for wilting during moist weather, or plants which feel loose and unattached, as signs of a problem.
“I would strongly recommend planting Heucheras in the ground, where the risk and severity of vine weevil damage are generally lower,” shares Peter.
“Containers are best if the soil is too heavy or for short-term seasonal displays and growing plants on, ready for planting as larger specimens.”
Rust
Heuchera Rust is a serious cause of concern in the United Kingdom.
This fungal disease is not only destructive, but it also causes delightful foliage to become painfully ugly and riddled with depressions and pustules.
To guard against it, sequester newly-brought Heuchera for a month, and make it a point to prune old or dead leaves in autumn.
Planting in dense borders reduces airflow and could also worsen the problem.
Heuchera Rust can be combated with several chemical fungicides.
First, though, you need to remove all infected parts and incinerate them.