Transatlantic Plantsman

My new blog on new plants

I’ve started a new blog.

Going by the impressively catchy title of New Plants and Trials, it began last week on the Royal Horticultural Society’s website. You’ll find it here.

I’m sharing the space with the Trials Office at the RHS garden at Wisley: I’ll be posting about new plants and Ali Cundy, Trials Recorder for the RHS at Wisley, will be posting about the many and varied trials on flowers and food crops which the RHS runs every year.

Why not take a look? I've just started a series of three posts on new hardy geraniums. And while you’re there look over the other RHS blogs including one by the Curator of the garden at Wisley, Jim Gardiner. I’ll post an occasional catch-up list here – just so you know what you’re missing if you don’t pop over and check it out.

That’s my new blog - New Plants and Trials - over on the Royal Horticultural Society’s website.

Most popular new plants in Britain

The latest edition of the Royal Horticultural Society’s Plant Finder came out earlier this month. You know the story: over 70,000 plants, over 700 nurseries, the last word in correct plant names and, for European gardeners, sources for all those 70,000+ plants. It’s indispensable for gardeners across the world – just to help us all get the names right.

There are over 4,100 new plants in the 2008/2009 edition and the top two, judged by the number of nurseries stocking the newcomers, are Brunnera macrophylla ‘Mr Morse’ and Salvia x jamensis ‘Hot Lips’, than any other newcomers.. More nurseries are stocking these two new introductions than any others.

Brunnera macrophylla ‘Mr Morse’ looks like a white-flowered version of the very popular blue-flowered ‘Jack Frost’. The foliage is the same – brilliant silver with narrow green veins – it’s just the flowers that are different. Great in shade, even dryish shade, and deer resistant too.

‘Mr Morse’ originated with Belgian plant breeder Chris Ghyselen. He crossed his own ‘Inspector Morse’, which is like ‘Jack Frost’ but with a fraction more green in the leaves, and white-flowered ‘Betty Bowring’. The result is ‘Mr Morse’. It’s new in Britain this year and available from eighteen British nurseries. In the US you can get it from Garden Crossings and other suppliers.

Salvia x jamensis ‘Hot Lips’ is amazing, dramatic bicolored flowers on twiggy shrubs broader than their 90cm (3ft) height. Tony Avent, on the Plant Delights website, explains its origin. “This wild selection… was introduced by Richard Turner of California after the plant was shared with him by his maid, who brought it from her home in Mexico.” Tony lists it as a form of S. microphylla but the RHS considers it a form of S. x jamensis (a hybrid of S. greggii and S. microphylla). Tony also points out that the flowers become more red in high summer when the nights are warm and, as you can see from the picture, the markings can vary from flower to flower.

’Hot Lips’ is available from fifteen British nurseries and Wyevale Garden Centres. In the US you can get it from Plant Delights and many other nurseries.

Top Ten New Perennials - US sources

At the end of March I posted a link to my piece on the Top Ten New Perennials on the website of Britain’s Daily Telegraph newspaper. The article gives UK sources of these plants but I’ve been asked, in comments to the post and by email, for US sources. So here goes. Not all these plants may be new to the US, of course, and some have not yet crossed the water. I’ve added a few short quotes from my Telegraph piece. Don’t forget you can read the original piece here.

Rather naughtily, I'm tempting you with pictures of two for which I cannot, yet, find US mail order sources! - Geranium pratense 'Laura' (above) and Sedum 'Marchant's Best Red' (below).

Cenolophium denudatum
“resembles a large flowered, perennial version of the annual Bishop's weed (Ammi majus)”
From Thompson and Morgan Seeds

Cortaderia selloana 'Evita'
“superb dwarf introduction from Germany I spotted last year”
Described by Sugar Creek Gardens website, but not yet for sale from them - or anyone else as far as I can see.

Echinacea purpurea 'Green Envy'
“this newcomer from the garden of Mark Veeder in New York State is absolutely unique”
Wayside Gardens
White Flower Farm

Eryngium planum 'Jade Frost'
“dramatic for three seasons of the year”
Wayside Gardens

Euphorbia 'Helena's Blush'
“ideal in permanently planted containers and for sunny corners in good soil”
Garden Crossings

Geranium pratense 'Laura'
“lovely double white form of…  meadow cranesbill”
No US source, yet, that I can find. Please let me know if you find a mail order nursery selling this plant.

Helleborus x ericsmithii 'Ivory Prince'
“a superb plant for both flowers and foliage”
White Flower Farm

Heuchera 'Rave On'
“for its combination of sparkling foliage and colourful flowers, 'Rave On'… is definitely the pick.’
Great Garden Plants
White Flower Farm

Iris 'Brown Lasso'
“The colouring is exquisite”
Schreiner’s Iris Gardens

Sedum 'Marchant's Best Red'
“the best dark-leaved sedum for all-season foliage colour”
No US source, yet, that I can find. Please let me know if you find a mail order nursery selling this plant.

Top Ten New Perennials

Today, I have a piece on the Top Ten New Perennials in the Daily Telegraph.You can read it here. Be sure to click on the In Pictures: Top 10 new perennials link at the top of the page to see a slide show of all ten of my picks.

You can also read my previous article on Clematis cirrhosa here

And my piece for the Telegraph on hellebores here

And my piece for them on winter arums here

And my piece for them on bergenias here

And my piece on winter flowering pansies here

And another piece, on growing your own mistletoe, here

The Daily Telegraph is one of Britain's best-selling daily newspapers and winner of the 2007 Garden Media Guild award for the Gardening Newspaper of the Year.

 

And my piece for the Telegraph on hellebores here

And my piece for them on winter arums here

And my piece for them on bergenias here

And my piece on winter flowering pansies here

And another piece, on growing your own mistletoe, here

The Daily Telegraph is one of Britain's best-selling daily newspapers and winner of the 2007 Garden Media Guild award for the Gardening Newspaper of the Year.

Odd new polyanthus

New primulas of one kind or another just keep on coming and in garden centres around the country at the moment are two polyanthus varieties which really are different – whether they have anything else going for them I’m not so sure.

The Royal Oakleaf Series have two distinctly unusual features. Firstly, the leaves are strikingly lobed… which is fine: interesting, not dramatic, but an intriguing departure. Secondly, each flower is slit into six slender lobes… interesting, but significantly reducing the impact. There are two forms.: ‘Glamis’ is a red and yellow bicolour – the shade of red varies noticeably- while ‘Balmoral’ is a bright yellow version.

The trouble is that these are more interesting oddities for primula fanatics than significant new garden plants. But they seem to be in quite a few British garden centres just now, so see what you think.

These plants come from BrilliantGardens.com – where you can find other new primulas and also new begonias.

Prolific new clematis

Evergreen clematis are invaluable garden climbers and at this time of year Clematis armandii, in its various pink- and white-flowered forms is really spectacular.

I’ve been looking at the plant sales areas at garden centres around Britain over the last two or three weeks and one plant I especially noticed was a new form of this excellent plant – ‘Enham Star’. Discovered in the horticulture division of Enham, a national disability charity, the flowers are white with a slight pink blush and ‘Enham Star’ is said to be unusually prolific – and it certainly looks that way from the large plants I saw on sale. Look out for it in the new RHS PlantFinder, out next month.

Oddly, though, go to the Enham website and there’s no mention of the clematis at all.

Exciting new drought tolerant perennials

Tough, prolific and colourful drought-tolerant plants are becoming increasingly valuable and preparing a lecture on new perennials today, it struck me again how baptisias are under rated. And there’s been a flurry of new introductions in recent years which have greatly expanded the color range. They combine drought tolerance with an imposing presence and prolific flowering – and unlike lupines, which are rather similar in their general appearance, they don’t suffer from those monstrous gray lupine aphids and are less troubled by powdery mildew.

At the Chicago Botanic Garden Jim Ault, who brought us the Meadowbrite echinacea hybrids, has now introduced four hybrids in his Prairieblues  Series. Starlite Prairieblues is a hybrid between B. australis and B. bracteata with brilliant blue and white flowers on tall spikes. In a much darker blue, Midnight Prairieblues is a cross between B. australis and a seedling from a cross between B. tinctoria and B. alba. Opening yellow then developing rusty orange tints Solar Flare Prairieblues is another complex hybrid involving those same three species. Finally, Twilight Prairieblues is a bicolor in deep purple and yellow, this time derived from B. australis and B. sphaerocarpa.

At the North Carolina Botanic  Garden Curator Rob Gardener selected a hybrid of B. sphaerocarpa and B. alba he named ‘Carolina Moonlight’, with long buttery spikes over blue-tinted foliage. He also selected ‘Purple Smoke’, a hybrid of B. minor var. aberrans with blackish stems topped with smokey purple flowers.

All these baptisias are native to the North America; some overlap naturally in their distribution and some are isolated from each other. But bringing them all together in a controlled way creates unique genetic combinations – and unique plants with prolific flowering in new shades.

But the old fashioned way also works. Tony Avent of Plant Delights Nursery in North Carolina spotted an unusually vigorous and upright plant of B. alba, with dramatic spikes of white flowers, growing in nearby Wayne County. He introduced it as ‘Wayne’s World’. In Arkansas native plant guru Larry Lowman selected B. sphaerocarpa 'Screamin' Yellow' with unusually brilliant yellow spikes.

Remember that all these baptisias love the sun, tolerate drought and are hardy (zone 4 or 5) and easy to grow. I have to say that mine are not in full sun and so are less prolific than I would like. They also make great cut flowers; cut the stems when about a third or a half the flowers are open and put them directly into warm water contain flower preservative. They should last well.

Buy these baptisias by mail order in North America from Great Garden Plants,  Plant Delights Nursery, White Flower Farm and North Creek Nurseries. Not all are yet available in Britain, but check the RHS PlantFinder to find who's selling what - the new 2008 edition, with new listings, will be available online in early April.

A blue impatiens!

I keep forgetting to bring this to your attention and now that spring is approaching for many (excluding, of course, those of us still battling with ice-rink driveways) I’ve remembered… a BLUE impatiens. Really? Well, yes. It goes by the tongue-twisting name of Impatiens namchabarwensis and in Britain there’s an improved form called ‘Blue Sky’.

This is a classic plant hunting discovery, the species was found for the first time by two botanists who trekked 100km from the nearest road to a gorge in Tibet which is almost the length of the whole of Britain and twice as deep as the Grand Canyon. This was as recently as 2003, it was named in 2005 (after the gorge where it was found). You can find out more about its discovery here.

Seed went to the British National Collection of Impatiens, then to the plant breeding station at Thompson and Morgan Seeds in England where plant breeder Charles Valin set about transforming the tall and lanky plant – with spectacular blue flowers – into something more gardenworthy. ‘Blue Sky’ (previously called ‘Blue Moon’) is the result.

Although the striking blue flowers were clearly dramatic, the plant was tall and lanky, did not branch well and flowered sparsely. In just a few generations of careful breeding and selection, Charles has improved the plants enormously and selected ‘Blue Sky’ which reaches only about 45cm/18in in height, branches well and is more prolific in flower than the wild species. It grows well in shade or in partial shade if the soil is moist and on cool morning the blue flowers will sparkle at their best, becoming more purplish as the day warms up.

‘Blue Sky’ is not yet available in the US, but the wild species is. And by the way, when you see the name Blue Diamond attached to it this is not the name of a special selection, it’s a “common name” give to it by, well, someone who didn’t fancy making a stab at pronouncing the botanical name!

Plants of Impatiens namchabarwensis ‘Blue Sky’ are available by mail order in Britain here.

Plants of the wild form of Impatiens namchabarwensis are available by mail order in the US here

Great new plants for shade gardens

Great news for shade gardeners. Three superb new evergreen epimediums bred in Britain and launched there last year are now available in the US for the first time – from Wayside Gardens. Believe me, they’re gorgeous – they really impressed me when I saw them in England last spring - and they’re tough too, hardy to zone 5. The pictures, I'm afarid, do not reveal how amazingly prolific they are. They, and more newcomers, are also available in Britain this spring from Wildside Nursery (by mail order) and Foxgrove Plants (for callers to the nursery and at RHS and Alpine Garden Society flower shows).

Bred by Robin White of Blackthorn Nursery, who created the Party Dress double hellebores, all are hybrids between evergreen species introduced from China relatively recently and chosen from thousands of seedlings resulting from carefully controlled pollinations.

All three have been chosen because they hold their flowers well clear of the foliage, they have an extended flowering season so that if the first flowers are frosted you’ll still get a good display, and all three also have attractively coloured spring leaves. They were originally created in the early 1990s and have proved their worth over many years before finally being introduced.

‘Amber Queen’ (above left), in amber peach and yellow, is a hybrid between 'Caramel', a form of E. wushanense collected in China by the celebrated Japanese botanist Mikinori Ogisu, and another of his finds, E. flavum. The result is a clump-forming plant with exquisite flowers carried in great numbers. ‘Amber Queen’ is available from Wayside Gardens in the US, and from Wildside Nursery and Foxgrove Plants in the UK.

‘Fire Dragon’, in yellow and purple, is a prolific hybrid between E. davidii, introduced in 1985 by British botanist Martyn Rix, and E. leptorrhizum, another of Mikinori Ogisu’s introductions. ‘Fire Dragon’ is available from Wayside Gardens in the US, and from Wildside Nursery and Foxgrove Plants in the UK.

‘Pink Elf’, in pink and purple, is an impressively prolific and strongly spreading ground covering hybrid between E. leptorrhizum and probably E. pubescens, another introduction by Mikinori Ogisu. ‘Pink Elf’is available from Wayside Gardens in the US, and from Wildside Nursery and Foxgrove Plants in the UK.

They may look delicate but these exquisite shade lovers are tough – just be sure they’re never parched and never waterlogged. I’m really looking forward to trying them here in my ever expanding Pennsylvania shade garden.

In Britain, Wildside Nursery and Foxgrove Plants will also have stock of three new introductions from Robin White and these should be available in North America later this year. I’ll let you know when.

Another great nursery abandons print and goes electronic

In my last post I mentioned a couple of US nurseries which no longer produce a print catalog. Well, I forgot to mention that for Seneca Hill Perennials their 2008 catalog, being mailed in the middle of this month, will be their last printed version.

Nursery owner Ellen Hornig says on the front of the Seneca Hill Perennials website: “Global warming forces us to examine our resource use, and this is one arena in which it can be cut. We will be redesigning the website somewhat to compensate for the lack of a catalog, including adding… an archive wherein inactive entries can be kept for reference purposes.” Fine by me, just send me an email whenever the site is updated so I can take a look.

There are over 130 new additions to the catalog this year including a lovely new form of one of the best of all shade lovers, Primula sieboldii. Selected at the nursery, ‘Seneca Star’ (left) has huge, prettily dissected deep pink flowers with a white central star. Looks gorgeous. You can see all this year's newcomers here.

But don’t let one little thing that Ellen says about going totally electronic pass you by, it’s important: she’ll be adding a web archive of plants she no longer sells. This is great news! – not only for gardeners who bought plants from her years ago and need to check up on what she says about them. But for researchers, plant historians, horticultural botanists, other nurseries who might now be selling the plants - and for garden writers like me - this will develop into an invaluable resource. I wish other nurseries, especially those who introduce new and rare plants, would do the same. Thanks Ellen.

Note to British nurseries: Seneca Hill Perennials have raised and introduced some excellent new plants but most are not yet available in Britain. They would welcome the opportunity to exchange new plants with similar British nurseries.