|Official Plant Name||Heuchera|
|Common Name(s)||Coral Bells|
|Plant Type||Perennial Flower|
|Native Area||North America|
|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|
2.5 – 4M
0.5 – 1M
June – August
Most Soil Types
Moist but well drained
Neutral / Alkaline
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, the ‘screen’ has appealing 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. 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 58 accepted species (not including synonyms), hybrids and cultivars number several hundred and counting.
These evergreens usually range from 20 to 40 centimetres in height. A few dwarf varieties grow to only about 10 centimetres while at the other end of the spectrum some varieties grow to 60 centimetres. A plant’s spread ranges from equal to the height to double the height, depending on the variety.
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.
As for the ‘main attraction,’ the leaves, they are quite large and are borne on long petioles. They are of a rounded shape and are palmately lobed. Usually the lobes are shallow but infrequently are deep. Lobes may number from 3 to 9 with 5 or 6 being the most common. The very size of the leaves plus their scalloped, appealing shape makes for an excellent canvas on which the colours, be they light or intense, their changing hues, and their patterns, can play out their seasonal drama.
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.
Background and Origins
Heuchera is the largest genus of Family Saxifragaceae. Its evolution is not well understood compared to most other genera. Biogeographic and phylogenetic research imply that the genus originated in the Pacific Northwest. Even Heuchera taxonomy has posed and still poses a challenge to Botanists because, besides other factors, it is morphologically polymorphous.
Heucheras grow throughout North America except Nunavut and Quebec. 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.
These plants arrived in Great Britain in 1882. For many decades they were appreciated only by – shall we say – plant connoisseurs, but in the past two decades Heuchera has really taken off, receiving the RHS’s Award of Garden Merit for 17 varieties. And about time, for this lovely genus has a lot going for it, as one may readily infer from our selection of the ‘Sweetest Sixteen,’ underneath.
H. villosa is one of the parent species of many popular cultivars. It is one of those species that makes its home on rock and crag, doing so around the Appalachians. Its common name ‘Hairy Alum Root’ refers to its salient characteristic: hairy stalks and hairy leaves. In fact, ‘villosa’ is Latin for ‘hairy,’ ‘shaggy,’ or ‘furry.’ The pink-white florets it bears arrive very late in summer.
H. micrantha is another parent species of various varieties, and it too is a ‘rock and crag’ type, occurring along North America’s Western Seaboard. It too has hairy leaves but less so than H. villosa. It has a couple of points of interest; first, the red-purple tone of the foliage, and second, the very tall nearly one-metre high peduncles which bear pink-white florets.
H. americana is the species that could be called ‘Basic,’ for it has no very unusual characteristics. Though immature leaves have a purple tinge, they soon become a bright ‘leafy’ green. The long panicles bear florets of an indeterminate whitish colour. This nondescript species is another ‘rock and crag’ denizen except that it prefers the Central United States.
H. brevistaminea is the last species we outline for a couple of good reasons. It is rare, and is threatened and endangered outside a very small location in Southern California. This is a pity because it is a tough species that can thrive in inhospitable regions yet has lustrous bright green foliage and produces panicles of candy pink flowers.
H. villosa ‘Palace Purple’ is one of the most popular and widely-available Heuchera varieties, and was named the RHS plant of the centenary for 1983 to 1992. Its deeply-lobed leaves are a metallic reddish purple above which panicles of pinkish florets stand erect in summer. Stalks and peduncles too are of a reddish purple. The plant forms mounds of 20 to 30 centimetres high and wide.
H. micrantha ‘Palace Purple’ – Yes, Martha, the H. micrantha species also has a ‘Palace Purple’ cultivar and oddly enough it too is an award winner, being the Perennial Plant Association’s Plant of the Year 1991, to wit. It too forms mounds of 20 to 30 centimetres and 40 wide. The leaves, however, can differ in colour from olive green to a shades of near true purple. It bears off-white panicles from early summer.
H. ‘Bella Notte’ is quite similar to the two ‘Palace Purple’ varieties in habit and height; moreover, even its gently scalloped leaves are a dark maroon-purple. However, it outdoes them in the floral department. This variety not only has a long blooming season from late spring clear through to early autumn, the hue of its flowers, from bright pink to cherry red, is markedly more attractive.
H. ‘Autumn Leaves’ is not suitably named; it would be more apropos to call it ‘Seasonal Leaves,’ for in spring the attractively-scalloped leaves begin the show with a reddish salmon colour, turn a light grey-brown in summer, and then again change colour to deep shades of red, from vermilion and flame to ruby red. Summer’s creamy-white flowers are truly a sideshow on this largeish shrub that is often 50 x 50 centimetres.
H. ‘Lipstick’ is suitably named and is also a brilliant red, except that this is a Heuchera variety that has the rare distinction of being named after its flowers! Of a classic Lipstick Red hue, the florets are a little bigger than usual and the plant blooms profusely, and re-blooms. The foliage makes for a wonderfully complementary backdrop in summer as the leaves are bright green with silvery dappling and marbling. It is much broader than high, at 36 centimetres wide by 20 tall. It is a recipient of the RHS’s Award of Garden Merit.
H. ‘Raspberry Regal’ Doubling up on Heuchera varieties with the rare distinction where the flowers take centre stage, this one also bears bigger-than-average flowers on even longer peduncles that are often just shy of one metre! Though the scalloped backdrop has some silver marbling on a brilliant green canvas, it’s all about the late-spring early-summer masses of deep, rich red blooms with this aptly-named variety.
H. ‘Caramel’ Staying with the foodstuffs theme but reverting to foliage as the main attraction, this increasingly popular clump-forming variety has very rounded, shallowly-lobed leaves. Starting off in tones of pale pink to pale orange in spring, the leaves gradually take on colour, warming up to such a rich, golden caramel hue that it may make you long for Callard & Bowser’s. Tiny light pink florets make an appearance in summer.
H. ‘Electric Lime’ Staying with both food and foliage, this ‘feature-packed’ variety is quite big, to begin with. It grows to about 50 centimetres high by about 80 wide. The leaves have a lovely palmately-lobed shape. They start off ‘electric’ yellow with red veins, and mature to a lime green hue decorated with thick and deep veining in contrasting deep red. It bears pedicles of especially dense florets in pure white. Adding to its ‘features,’ this variety is especially tough.
H. ‘Circus’ displays especially regular shallow-scalloped leaves as if they are produced from a cookie-cutter. Though it has similar lime-green foliage with prominent blackish-red veins, it has its own twist: in the summer, bright pink florets rise above the leaves and last until the end of summer, and come autumn, the leaves change colour, also to purple-pink. So if you’re lucky, at end-summer, start-of-autumn, you may catch colour-matching florets and foliage!
H. ‘Paris’ is on the small side at about 25 centimetres high and wide, and is a clump-forming variety. Its foliage offers a colour reversal from ‘Circus’ as the veins are prominently and broadly etched in green on a silver ground. It bears relatively large rose pink florets on bronze-toned peduncles over a particularly long blooming season. This disease-resistant variety is a recipient of the RHS’s Award of Garden Merit.
H. ‘Sweet Tart’ Only 10 to 12 centimetres tall and with a mounding habit, this variety’s scalloped leaves change colour from a ‘popping’ greenish-yellow through lime-green, to which the cerise to cherry-red florets on tall panicles make a lovely and lively contrast. This variety is a choice pick from the (trademarked) ‘Little Cuties’ range of very compact dwarf cultivars, which are particularly robust.
H. Frilly (‘Alchefril’) is the latest variety and it may cause a sensation when it is introduced this year, 2021, at the Chelsea Flower Show. The colour ranges from caramel and light orange in summer or in the shade, to a deeper orange and even scarlet in the winter or in sun, as in the parent ‘Tangerine Wave.’ This sport’s charm is in its ‘frilly’ irregularly scalloped leaves; they are unusual in being tightly frilled. It bears cream-coloured florets.
In closing out this section, those who like Heuchera would do well to look into Heucherella. A hybrid of Heuchera and Tiarella, this line has some awesome varieties like ‘Heart of Darkness.’
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, Heuchera villosa cultivars are hardier at both temperature extremes than Heuchera micrantha cultivars. That said, as British weather does not get very hot or humid – 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 or humidity are slim.
Most varieties’ USDA Hardiness Zones are from 4 to 9.
When and Where to Plant Heuchera
Heuchera can be planted or transplanted in spring or autumn.
In general, Heuchera are as if tailor-made by that Master Tailor Up There for borders, accents, and rock gardens. It is true that these plants provide superlative backdrops 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 or home-maker’s imagination.
Feeding, Care & Growing Tips
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. micrantha ‘Palace Purple’ 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. 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 fertilizer.
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.
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 like BotaniGard ES.
Heuchera Rust is a serious cause of concern in the United Kingdom. This fungal disease is not only destructive, it causes delightful foliage to become painfully ugly. To guard against it, sequester newly-brought Heuchera for a month, and make it a point to prune old or dead leaves in autumn.
Heuchera Rust can be combated with several chemical fungicides. First, though, you need to remove all infected parts and incinerate them. Provanto Fungus Fighter Concentrate, Toprose Fungus Control & Protect, Bayer Fungus Fighter Plus, and Scotts Fungus Clear Ultra are among the better fungicides that can be applied.
Where to Buy Heuchera
Rising in popularity, many Heuchera varieties are being sold at brick-and-mortar garden centres and are also sold online by well-reputed nurseries.
Perhaps the best way to ‘buy’ Heuchera is simply to divide them every two years. They are easy plants to divide, and division has the dual benefit of extending the life of the parent plant and providing a new one.