Almost two hundred years ago Alexander Campbell, curator of the Manchester Botanical and Horticultural Society’s Garden, crossed a foxglove and a gloxinia (Digitalis grandiflora and Sinningia speciosa) to create what was known as Campbell’s hybrid foxglove.
It looks a little like a rusty D. grandiflora (below, right) but pollen from another foxglove - D. obscura, perhaps? - must have achieved the fertilisation that pollen from a gloxinia could never manage.
The first genuine foxglove hybrid between, D. purpurea and D. grandiflora, was made in 1849 but the seedlings were all sterile and it was not until 1924 that two hybrids that are still grown today were created at England’s John Innes Horticultural Institution: D. × mertonensis and D. ‘John Innes Tetra’.
Since then a large number of hybrids between different foxglove species have been created although, sadly, many have been lost including an interesting range created by the short lived Europa Nursery (anyone know where the owners, Tim Branney and Adam Draper, are now?).
Now, digitalis breeding is enjoying a bright revival with new hybrids being developed on both sides of the Atlantic. Goldcrest (‘Waldigone’) (above, left) was one of the first recent hybrids to make its mark. Three different breeding programmes in The Netherlands, in Suffolk (UK), and in Michigan, bring together the familiar British Native foxglove, D. purpurea, and D. canariensis from the Canary Islands. Foxlight Ruby Glow (‘Takforugl’) (above, right) is one of them. And, please, both parent plants are Digitalis. Let's not mess around with creating an imaginary new genus – Digiplexus.
Two new series of prolific dwarf hybrids are also just coming on to the market, the very short Knee High Series (‘Knee High Lavender’ above centre) from England and ‘Lucas’ and ‘Martina’ from The Netherlands.
I’ve recently published a long piece about the history of foxglove hybrids, from that early attempt using pollen from a gloxinia to the very latest developments. It appears in the current (March) issue of The Royal Horticultural Society magazine The Plantsman.
You can read my piece on foxglove hybrids online, but please take a moment to subscribe to The Plantsman: you can subscribe to The Plantsman here.
Finally, in this week of daily postings on the best of 2016 and looking ahead to 2017, two exciting perennials to look out for in the year ahead.
Hosta ‘Branching Out’
Tony Avent at Plant Delights in North Carolina started out to create a hosta with branching flowering stems back in 1989 and, usig five different parents and after a number of generations of crossing and selection, ‘Branching Out’ is the result. (You can read more on Tony’s blog.)
Its pale lavender flowers on their sturdy 30in/90cm branching stems make an attractive and prolific show in mid summer over broad, heavily veined, dark green leaves. All we need now is added fragrance.
Hosta ‘Branching Out’ is available in North America from Plant Delights, it is not yet available in Britain.
Ajuga reptans 'Choc Ice'
There are few plants with bronze or purple foliage and white flowers. It’s a matter of genetics, the bronze or purple leaf colouring tends come with flowers colours at the same end of the spectrum. Astilbe ‘Chocolate Shogun’ is close, its chocolaty purple leaves topped with pale pink plumes.
And here’s another candidate, a bugle with white flowers held above purple leaves and bracts. OK, it all turns greener late in the season but at flowering season, it looks impressive. Discovered by plantsman Geoff Hitchens.
Ajuga reptans 'Choc Ice' will be available again soon in Britain from Monksilver Nursery. It is not yet available in North America.
Having picked out five new and old plants that were especially memorable in 2016, let's look ahead to plants I haven't even seen yet but which look unusually promising for the year ahead. First, two shrubs…
Abelia Pink Pong (‘abenov41’)
Abelia Pink Pong (‘abenov41’) must win the prize for one of the worst plant names ever – Pink Pong! Or perhaps I’m just a little old fashioned? Anyway, this is the first Abelia with a long season of large colorful flowers and a lovely fragrance.
There are other fragrant abelias but none combines large pink flowers opening from purple buds from May to October with a strong fragrance, dependably evergreen foliage, reliable hardiness and colorful autumn bracts to extend the season. Sounds worth trying, to me.
Pink Pong is a cross between Abelia schumannii '’Bumblebee’ and A. x grandiflora ‘Semperflorus’ and was selected in France in 2006.
Abelia Pink Pong (‘abenov41’) is available in Britain from Thompson & Morgan. It is not yet available in North America but should be soon.
Caryopteris Pink Perfection ('Lisspin') and Stephi (‘Lissteph’)
Two new pink flowered forms of Caryopteris, bluebeard, are coming on to the market just as two older varieties become unavailable. It will be interesting to see whether they have more lasting quality.
For some years the very late flowering, and not very hardy, C. incana ‘Autumn Blue’ was the only pink flowered form around but has now disappeared. Pink Chablis (‘Dureo’) was introduced in the US about fifteen years ago, but is no longer available, and I’m not sure it ever made it to Britain.
Pink Perfection ('Lisspin'), sometimes offered a Best Pink, and the bushier and more compact Stephi (‘Lissteph’) were both developed by the renowned British breeder of new shrubs Peter Catt. I’ve not seen them yet but they’re said to be as prolific and hardy as the best blue-flowered forms with a good strong pink coloring. I look forward to comparing them this coming season.
Caryopteris × clandonensis Pink Perfection (‘Lisspin’), sometimes listed as Best Pink, is available in Britain from these RHS Plant Finder nurseries. It will be available in North America soon.
Caryopteris × clandonensis Stephi (‘Lissteph’) is available in Britain from Hayloft Plants, and will be available in North America soon.
Ending the first part of my daily review of the some of the most memorable plants, new and old, from last year we come to the 2016 Chelsea Flower Show favorite – the new white flowered form of Primula vialii .
Primula vialii 'Alison Holland’
As soon as I entered the showground on the Sunday morning before the show opened on the Tuesday, plantspeople were asking me: “Have you seen the new white primula?” So off I rushed to take a look – and it’s lovely. I wrote it up on my RHS New Plants blog back in June. It was shortlisted for the 2016 Chelsea Plant of The Year award.
Basically, instead of the red buds and lilac flowers of the wild Primula vialii from China, ‘Alison Holland’ has creamy green buds and cool white flowers. Gary McDermott of Harperley Hall Farm Nurseries, who introduced the plant at Chelsea, told me that it’s more vigorous and flowers for longer than the usual form. But it hates drought.
‘Alison Holland’ was found in 2011 in his garden in the north east of England by John Holland who named it for his daughter-in-law. Plants never set seed but this form has proved easy to propagate by tissue culture.
Primula vialii 'Alison Holland' is available in the UK from Harperley Hall Farm Nurseries.
Primula vialii 'Alison Holland' is not yet available in North America but should be soon.
Continuing with the third of seven daily posts about the plants that caught my eye last year, we come to a fine perennial that I noted thriving in a number of different situations.
xHeucherella ‘Solar Eclipse’
With so many heucherellas on the market, its important to take a deep breath before pronouncing one as “unique” – but here goes: xHeucherella ‘Solar Eclipse’ is unique.
This distinctive clump-forming variety has slightly ruffled, prettily scalloped, reddish brown, almost chocolate brown, leaves with a neat minty green margin. It keeps its color well and matures into a clump about 20cm high and 40cm wide. The flowers are white – but not really the point. The cut leaves last quite well in water, too.
Lovely in a terracotta pot, it also looked unexpectedly good in a blue pot and at the front of border in dappled shade. In cool areas with water retentive soil it will grow happily in full sun but is general happier in some shade.
‘Solar Eclipse’ is sport of ‘Solar Power’ (which has yellow leaves with a red central pattern) and was developed by Janet Egger and Chuck Pavlich at specialist perennial breeders Terra Nova Nurseries in Oregon.
xHeucherella ‘Solar Eclipse’ is currently available retail in the UK from these Royal Horticultural Society Plant Finder nurseries.
xHeucherella ‘Solar Eclipse’ is currently available retail in North America from many suppliers including Bluestone Perennials and Plant Delights.
Making up for my summer break in posting, this is the second of seven daily posts featuring plants that caught my attention this year. Today, the first calendula with white flowers.
Calendula ‘Snow Princess’
The arrival of the PowerDaisy Sunny, the first hybrid between shrubby and annual calendulas, caught everyone’s attention a year or two back and now we have a calendula in a more familiar style but in a new color.
In fact each of the white petals shades into soft yellow towards the base and features a tiny bronze flash at the jagged tip of every petal. The eyes of the large flowers are either gold or deep brown – mine were all dark-eyed but in other plantings I saw they were mixed.
The good people at Thompson & Morgan gave me some advance seed at the end of July, I sowed it in England a few days later and plants were in flower in about nine weeks, bloomed happily through October and they seemed to thrive in spite of a little mildew. When I flew back to the US in November they were looking a little sad but still flowering.
The plants bushed out nicely without pinching and I cut most of the flowers for the house where they lasted well. Next season I’ll be sowing them in March.
Calendula ‘Snow Princess’ was developed in Europe by the Dutch subsidiary of Takii, formerly Sahin BV, who specialized in hardy annuals for many years.
Calendula ‘Snow Princess’ is currently available retail in the UK from many seed companies including Mr. Fothergill’s, and also Suttons and also Thompson & Morgan.
Calendula ‘Snow Princess’ is currently available retail in North America from Baker Creek Heirloom Seeds.
Just because posting here paused for a while this year didn’t mean that impressions of new and old favorite plants failed to penetrate into the brain. Far from it. So, starting today, I switch to the opposite extreme with brief daily thoughts on five plants – new and old - that caught my attention this year plus two or three that I haven’t even seen yet but which look really exciting. Here’s the first.
Argyranthemum GranDaisy Pink
The four plants in the GranDaisy Series are all hybrids between marguerites, Argyranthemum, and annual chrysanthemums (Gledionis coronaria, better known as Chrysanthemum coronarium). Yes, a shrub crossed with an annual in a different genus. The botanists are working on its correct name.
The results are plants with flowers in unusually pure colors in the red, yellow and white varieties and with flowers opening over an exceptionally long season without pauses for breath. But Argyranthemum GranDaisy Pink has also inherited the ring around the eye seen so often in annual chrysanthemums and the effect is exceptional.
These are plants for summer containers and well-drained sunny summer borders, probably hardy in zone 9, perhaps zone 8, and tolerant of summer heat but not happy in high summer humidity.
The series has its own website, but the text needs more information and less whimsy: “GranDaisy is an uncomplicated, unassuming and understated plant that will give you summer every day” the site tells us and “GranDaisy is more than a plant, it's an experience”. Hmmm…
The GranDaisy Series of Argyranthemum hybrids was developed in Japan by Suntory, who also developed the Surfinia trailing petunias.
Argyranthemum GranDaisy Pink is currently available retail in the UK, in a collection with the red and yellow forms, from Thompson & Morgan.
Argyranthemum GranDaisy Pink will be available soon in North America.
Reticulata irises are one of the joys of spring, but we seem to have been growing the same varieties for decades. In fact, the ones I used to look after when I worked in the Alpine House at Kew Gardens over thirty years ago are, basically, the ones we still grow. Well, until now.
There’s a fascinating piece in the Royal Horticultural Society’s monthly membership The Garden this month, by Assistant Editor Phil Clayton, about Canadian iris breeder Alan McMurtrie and the amazing varieties he’s developed.
It’s been a long haul. Alan began his work many years ago, soon after I was working with the irises at Kew, in fact, but it takes five years for the seed produced by crossing one variety with another to build a big enough bulb to flower. And that’s only the start, because after two or three generations of crosses and selections and a new seedling is finally seen to be good enough to be named – then a large number of bulbs have to propagated so that they can be sold and that takes a long time. Alan has been developing these lovely little plants for thirty years and only now are his new varieties becoming available to gardeners.
He’s been continually expanding the range of colors and color combinations. The white ‘White Caucasus’ and the blue-and-white ‘Eye Catcher’ (top) were amongst the first to be named but Alan also has improved varieties in the familiar blue and purple shades, 'Splish Splash' (below), along with new varieties in vivid yellow, and orange, yellow with navy blue marks and with smokey tints ('Storm', left) or brown speckles… They’re just amazing.
You can read the article about Alan’s irises from The Garden online, and in next month’s issue of another Royal Horticultural Society magazine, The Plantsman, you can read a more detailed account. Alan McMurtie is refreshingly open about his work and Alan's website includes many pages of details and a huge number of pictures.
Alan is lecturing in Britain this month, so this is a great opportunity to hear about his irises from the man himself. He’ll be speaking at the RHS London Flower Show on 16 February, at a meeting of the Scottish Rock Garden Club in Dunblane on 20 February, and at the Alpine Garden Society’s show at Harlow in Essex, just north of London, on 27 February. At present, he has no North American lectures scheduled.
Like to buy some bulbs? In Britain take a look at the offerings from Jacques Amand, at Broadleigh Gardens, at Pottertons, and at Rare Plants. In North America you can buy some of Alan’s varieties at McClure & Zimmerman, at White Flower Farm and at Botanus.com. Of course the plants are flowering now, you ill be able to order bulbs later in the year.
Jacques Amand featured Alan’s irises at the Philadelphia Flower Show last year, and will do so again next year, but this year the theme is tulips. This week’s RHS London Flower Show will feature an extensive range, shown by Jacques Amand
Oh, yes… You want to know how to grow them. Here’s what Alan recommends:
“They should be planted 3in (8 cm) deep in well drained soil (a touch deeper is fine). They don't mind snow melt in the spring, but don't like to be near a downpipe in summer. Plant about the same distance apart. Resist the urge to plant too close together. If you've given them the right conditions they will form clumps.
“Remember new bulbs are forming at the base of each leaf. They represent next year's bloom. So don't go ripping them out and wonder why you don't have flowers next year. The longer they stay green, the bigger the bulbs will be.”
Images © Alan McMurtie Thank you for making details of your work so freely available.
Coleus are enjoying a spectacular - and well deserved - revival. And while Dibleys in the UK and Glasshouse Works in the USA have kept the old favorites available for many years, amazing new varieties of coleus in even more colors and color combinations, from seed and from cuttings, are now being introduced at an astonishing rate. There are even coleus for hanging baskets.
A fine new book on coleus appeared about five years ago (forty years after the previous one), three years ago almost a hundred were trialed outside by the Royal Horticultural Society and so coleus are now again getting the recognition they deserve. Those startling colors just keep tempting us and they look so good with some many other foliage plants and flowers.
In North America coleus (and of course their botanical name is Solenostemon) have remained popular as outdoor summer foliage plants for borders and containers. In Britain, they were relegated to conservatories and greenhouses because of the strange belief that they didn’t perform well outside. But I remember back in the 1980s – yes, yes, I know – that one of the star plants of the summer plantings along the Broad Walk at the Royal Botanic Gardens at Kew was coleus. Two old varieties in particular, ‘Sunset’ and 'Picturatus', were often used to edge the beds.
As I write Glasshouse Works in the US are listing 132 different coleus, Dibleys are listing twenty four coleus, fifty three coleus are promoted by the Proven Winners brand in the US but in the UK Proven Winners don’t feature any at all. But in just two years Terra Nova Nurseries (famous for the vast number of heucheras they’ve developed over the years) has introduced thirty seven new coleus in seven different series - in just two years! And their 2016 introductions have not yet been announced.
Terra Nova have spent eight years developing coleus and their introductions vary from tight and compact to big and bushy with two series (Color Clouds, below, and Color Carpet) intended for ground cover and hanging baskets. You can check out their series and all the individual coleus varieties at the Terra Nova home gardeners website.
At the moment, on both sides of the Atlantic, you’re probably most likely to see seed-raised varieties such as the monster-leaved Kong Series and ‘Chocolate Mint’ (above). But look out for these new series from Terra Nova and give them a try.
RHS Award of Garden Merit
These eleven coleus were awarded the RHS Award of Garden Merit, or had earlier awards reconfirmed, after being trialed the RHS Garden at Wisley and also on the Victoria Embankment in central London: ‘Black Prince’, ‘China Rose’, ‘Gay’s Delight’, Henna (‘Balcenna’), ‘Juliet Quartermain’, ‘Pineapple Beauty’, ‘Pink Chaos’, Redhead (‘Uf0646’), Trusty Rusty (‘Ufo6419’), Versa Crimson Gold (‘Pas733805’), ‘Winsome’.
In recent years, Barnhaven Primroses, originally from Oregon and now in France (via England) have been branching out. Nothing dramatic, but alongside primroses they’ve been expanding their choice of other primulas and also added hellebores to their range.
One exceptional, and much underrated, plant they’ve been championing is Primula sieboldii and they’ve recently announced the availability of some lovely forms from Japan, including the double-flowered ‘Flamenco’ (above). They’ve been quietly been building up stock for some time.
This is an exceptional species, with fresh looking, bright, divided leaves and a flurry of up to ten spring flowers held on upright stems. Sound like a polyanthus? Yes, but so much more delicate and stylish.
In the wild, it’s a woodlander creeping through wet woods in Japan, Korea, China, Russia and, as the canopy closes, the foliage fades away. In summer I find it will take drought, although it’s worth remembering that the plants dislike lime. And it’s very hardy: USDA Z4, RHS H7.
The only problem is that with no sign of it above ground from late summer until mid or late spring, it’s easy to forget precisely where you planted it and attempt to plant something else in its space.
Our plants here in Pennsylvania came from the late and much lamented Seneca Hill Nursery in upstate NY and I always pick a few stems to bring indoors from the expanding clumps. Some of the clumps have expanded so much that they’ve escaped the borders, meandered under the boards supporting the raised bed and emerged on the path.
Lazy’s Farm now seems to have the best choice in the US but, in Europe, always start at Barnhaven. They have seventeen varieties of their own raising, including ‘Trade Winds’ (right, click to enlarge) and twelve Japanese varieties available as plants, including the lovely ‘Flamenco’ (top) and some delightful forms with white picotee edges to the flowers. Nine more varieties are available as seed.
Barnhaven will send seeds, and also plants, to the US, with a phytosanitary certificate at a cost of 11.43 euros. If customers have a small seed lots permit there is no phyto charge for sending seeds. [After six months I'm still waiting for my small seed lots permit...]
Perhaps people are disconcerted by the fact that the plants disappear for much of the year, or perhaps the intolerance of too much lime puts people off. But considering how easy they are to grow, we really don’t see them enough. They’re much easier to keep over the long term than the special varieties of primroses and polyanthus which so often seem to fade away after a few years.
In Japan, the heyday of Primula sieboldii was from the beginning of the 17th century to the mid 19th century but now Barnhaven and others are re-inventing them after so many varieties have been lost over the centuries. And it’s not as if they need careful cossetting and conditions it’s tough to provide. They’re easy… give them a go.