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March 2013

Best heucheras for North America

Heuchera 'Apple Crisp' (above) and 'Tiramisu'. Images Terra Nova Nurseries and GardenPhotos.comLast month, I reported on heucheras recommended for British gardens by one of the top British Heuchera specialists. As I discussed in my recent piece about plant awards, recommendations intended for British gardeners are not much use in the US – and even here in America a plant which thrives in one part of the country may well be less successful in another. But the US is the home of the Heuchera, so I’ve now taken some expert advice on the best heucheras for American gardeners.

I went to Steve Rokopf who runs the mail order nursery Casita Azul in Wisconsin and who, as far as I can count, lists more heucheras than anyone else – 129 as I write this, with more on the way - and sends them all over. (And you should see his range of hostas…)

So keeping in mind the dramatic climatic differences across the country, here are Steve’s thoughts on the types of heucheras that do well in three important regions, together with his specific recommendations.

Mid Atlantic States (Delaware, Maryland, New Jersey, Pennsylvania, Washington D.C., New York, Virginia, and West Virginia. North Carolina is sometimes also included.)
“Extremes in seasonal conditions dictate which heucheras do best in the Mid Atlantic States.  Most of today's hybrids contain some Heuchera americana genetics, this is the species that does well growing in hot summers and freezing winters.  Most of today's newer varieties will grow nicely in Mid Atlantic States.”
‘Apple Crisp’ Crunchily crisped fresh green leaves overlaid in silver.
‘Gotham’ Primrose yellow flowers set against reddish black leaves.
‘Melting Fire’ Blood red young leaves mature to rich reddish purple. Seed raised.
‘Silver Scrolls’ Bright silver foliage, edged and veined in rich red.
‘Tiramisu’ Chartreuse foliage, overlaid with red.
Heuchera 'Midnight Rose' (above) and 'Caramel'. Images ©GardenPhotos.comThe South (Alabama, Florida, Georgia, Louisiana, Mississippi, South Carolina, and Texas.)
“Heat and humidity are the two big challenges, heucheras that thrive in the south must be able to tolerate both. Plants with Heuchera villosa genes are "heat-seekers" that do very well in the south.  And Southern gardeners are better off planting their heucheras in shadier locations."
‘Caramel’ Toffee-colored foliage is reddish below.
‘Georgia Plum’ Rosy purple leaves overlaid in silver.
‘Midnight Rose’ Reddish black leaves speckled in pink.
‘Midnight Ruffles’ Reddish brown, highly ruffled foliage shows red sparks from the undersides.
‘Tara’ Jagged, golden foliage is red-tinted in spring.
Pacific Northwest (Oregon and Washington and the Canadian province of British Columbia.)
“Moist conditions can be a challenge for heucheras.  Plants that can tolerate consistently moderate temperatures and moist "feet" are best for the Pacific Northwest.  The hybrids with Heuchera micrantha genes will tolerate the wetness better than most and many of today's hybrids have genetics from species that are native to the West Coast and the Pacific Northwest.  Excellent drainage is the key”
‘Blackout’ Glossy, almost black leaves and cream flowers.
‘Glitter’ Reflective silver leaves with black veins.
‘Hercules’ Rich green, boldly white-variegated leaves, plus carmine flowers.
‘Lime Ruffles’ Ruffled limey leaves with a delicate silvery haze.
‘Plum Royale’ Glossy purple leaves and white flowers.

That sounds like great advice to me. And it’s clear that with so many recent introductions, there’s now a good choice of types available for all regions.
Heuchera 'Glitter' (left) and 'Lime Ruffles'. Images ©Terra Nova Nurseries

Powerhouse Plant For All Seasons - Peony 'Sarah Bernhardt'

Peony 'Sarah Bernhardt' has both colorful foliage and colorful flowers. Images ©

Today I start a new series in Britain’s best selling gardening magazine, Gardener’s World. Starting in the May issue, on sale in Britain today (and also in the US soon), Plant For All Seasons takes up the theme of my new book, Powerhouse Plants, and each month reveals the many facets of a plant that looks good at two, three or perhaps even four seasons of the year.

Choosing plants with multi-season beauty is the way to create the maximum impact from every inch of your garden.

So in Gardeners World magazine this month, I show the many seasonal appeals of Fothergilla ‘Mount Airy. And here I’m offering you another plant to consider, this time a hardy perennial peony which looks good both in spring and in summer.

The rich red shoots of ‘Sarah Bernhardt’ are colorful and bright from the moment they peep through the soil in spring. As they expand, their impact increases and as the flower buds form they still look bright and fresh. Plant blue flowered Anemone blanda around it for a sparkling spring picture.

Then in June the big and blowsy, super scented, dark centered, rose pink flowers open, sometimes with a few dark flecks, and give us the sumptuous treat for which peonies are so much loved.

OK, it’s true, it’s not perfect: the flowers are often too big and heavy for the stems, so discreet support is advisable. And they don't last for ever - that's why an extra, earlier foliage display is so valuable. But this is nevertheless a sumptuous flower, introduced by Victor Lemoine in France back in 1906. It must be good to still be so popular after so long.

Please take a look at Plants For All Seasons in Gardeners World magazine each month. And check back here for occasional posts about other Powerhouse Plants – the Plants For All Seasons.

You can order my book, Powerhouse Plants in Britain from

You can order my book, Powerhouse Plants in North America and the rest of the world from

 Or you can find out more about the book at the Powerhouse Plants webpage.

 Subscribe to Gardeners' World magazine


Floral meadows

Floral Meadow at the RHS Garden at Wisley. Image ©
Last year both London’s Olympic Park and the Royal Horticultural Society’s garden at Wisley in Surrey benefited from some lovely plantings of annuals in wild-style meadows. The August day I saw them at Wisley was noticeably dull and overcast and drizzly but the great sweeps of annual flowers still sparkled brightly.

They came from a company called Pictorial Meadows who’ve developed a range of annual and perennial blends in a variety of styles and color themes – some are ideal for containers, others are better on a grand scale. At Wisley, the mown grass paths between them make a big difference.

Years ago, Mr Fothergill’s offered some wonderful color-themed annual mixtures, sourced in Holland. They supplied separate packets of seed of tall, medium and short varieties – and included an astonishing range of around one hundred different annuals in each color-themed pack. They were tremendous – but are, sadly, offered no more.

Pictorial Meadows was founded on the original research on developing floral meadows by Professor Nigel Dunnett at Sheffield University; the university part owns the company. Their offerings of separate mixes in different heights and in different colors are based on years of research and the result was a dull day delight. In North America, American Meadows have a similar range.

But one important thing to keep in mind. Don’t expect these mixture to be made up of native plants. Some are, and those in both the Pictorial Meadows range and the American Meadows range are clearly marked. But don’t expect those simply labeled “wildflower” to be native.

I mention all this now, because now’s the time to get started. You can take a look at the seed sowing instructions from Pictorial Meadows and the advice from American Meadows before you order.

Transatlantic plant awards

Weigela Wine & Roses ('Alexandra') has both a British and a Pennsylvania award. Image © Garden
There’s a big difference between Britain and North America in the ways in which awards are given to plants. In Britain, there’s really only one award that’s worth anything: the Royal Horticultural Society’s Award of Garden Merit (AGM). The award has just been completely revised and updated, and the new RHS hardiness ratings applied to each of the just over 7000 ornamental and edible plants that now have the award.‬

‪Of course in a small country - England is the size of Pennsylvania – one award is fine for everyone. In North America, with its vast variety of climates, having just one award is far less useful. However, it’s only fair to say that the All-America Selections do a good job within narrow parameters by focusing only on seed-raised plants – ornamental annuals, herbs and vegetables. But, being industry-funded, they are not impartial and independent. And the Perennial Plant Association has its Perennial Plant of The Year™ award, chosen each year by the Association’s members.‬

‪But it’s local awards that count, so here in Pennsylvania we have the Pennsylvania Horticultural Society’s Gold Medal Plants program, which features 212 plants but only cover trees, shrubs and vines – no perennials, annuals or edibles. In Missouri there’s the Plants of Merit scheme, covering 228 plants, although the only edibles included are ornamental ones. From the Elisabeth Carey Miller Botanical Garden in Seattle, WA, there’s the Great Plant Picks scheme with just under five hundred plants, but no edibles or annuals. ‬
Coleus 'Pink Chaos' is a Dallas Arboretum FlameProof Plant Award winner, but is rarely seen in Britain. Image ©Proven Winners
‪In the south there’s Athens Select, from the University of Georgia, which picks the best heat- and humidity-tolerant plant varieties while the Dallas Arboretum and Botanical Garden has its FlameProof™ Plant Award, which at present includes over 350 plants, but only those that perform “from May right up until first frost”.‬

‪This American focus on state-by-state awards of course makes perfect sense, which makes it especially pointless for North American nurseries to crow about their plants having the AGM, an award for top performers in Britain  – it’s just not relevant. Although occasionally a plant is good enough to be awarded on both sides of the Atlantic: Weigela Wine and Roses (‘Alexandra’) has an RHS AGM, and is also a Pennsylvania Gold Medal plant.‬

‪But I was interested to see that Helleborus x hybridus, given the Perennial Plant of The Year™ Award in 2005, has just been cut from the AGM list; rightly, it is seen as far too variable and gardeners just can’t be sure of getting a good plant under that name. And the whole point of all these awards is to recommend plants that gardeners can depend on.‬

Best heucheras for Britain (America’s choice coming soon)

Heucheras in Pots at Heucheraholics nursery. Image ©
We’ve all seen how, in the last twenty years, heucheras seem to be everywhere: borders, pots and even hanging baskets. And it’s true that for foliage color they’re simply unsurpassed in their range of colors and patterns. After initial pioneering work from Charles Oliver in Pennsylvania, Dan Heims and his team plant breeders at Terra Nova Nurseries in Oregon have led the way, with over 400 introductions. Now breeders in Europe are getting in on the act.

In Britain two nurseries, the splendidly named Heucheraholics and Plantagogo, are streets ahead of everyone else in the wide range of heucheras they offer and the promotion that they’ve given heucheras over the last few years. In the past, I’ve asked both of them to advise on the best heucheras: Jooles and Sean Burton suggested heucheras that change impressively over the seasons, and Vicky Fox of Plantagogo suggested heucheras with both good flowers and good foliage. Heuchera plants ready for sale at Heucheraholics nursery. Image ©

But when I visited the Heucheraholics nursery, in Hampshire in southern England, last summer I asked Jooles and Sean to be more specific, to be ruthless: which are the best of the best? They picked out four:

‘Blackberry Jam’ (‘Dolce Blackcurrant’ in the US) has silver leaves with black veins and crimson undersides, with a lovely shimmer (below, left, click to enlarge). The vigorous and tough, British-bred ‘Crimson Curls’ is very well ruffled, with green and bronze leaves which are dark red below. ‘Lime Marmalade’ (below center) has ruffled lime green foliage and the best sun tolerance of the lime leaved varieties. ‘Sashay’ (below right) has wonderfully ruffled green foliage, the ruffles revealing the purple undersides.

Next time I see them I’ll have to ask them which they’d choose if they could only grow one!

As it happens, Britain’s Royal Horticultural Society has just revised its premier plant award, the Award of Garden Merit, and updated its list of the best heucheras for Britain. Here they are: ‘Can-can’, ‘Fireworks’, ‘Magic Wand’, ‘Molly Bush’, ‘Purple Petticoats’, ‘Raspberry Regal’, ‘Regina’, ‘Sashay’ and ‘Scintillation’. There were additions to the old list from ten years ago, but they did cut these: ‘Blackbird’, ‘Burgundy Frost’, ‘Chocolate Veil’, ‘Quilter’s Joy’, H. sanguinea ‘Alba’ and ‘Smokey Rose’. They need a few newer varieties, don’t they…

I’ll be looking at America’s favorite heucheras her soon, and at the revised RHS Award of Garden Merit next time.
Heuchera 'Blackberry Jam', 'Lime Marmalade' and 'Sashay'. Images © (left) and Terra Nova Nurseries