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A newly discovered annual that's prolific and good for cutting

Erigeron annuus
Eastern daisy fleabane - Erigeron annuus


When I lived in Pennsylvania, there was a wild flower that popped up occasionally in open grassy places where the soil was disturbed, sometimes with native rudbeckias. Eastern daisy fleabane was a tall annual with pretty white, yellow-eyed daisy flowers, but I never thought to grow it in the garden.

Then I spotted it – Erigeron annuus - in the Special Plants catalogue, they were listing seedlings and recommending it as a cut flower. So I had to try it. And it’s been brilliant.

After a slow start it’s now reached 1.2-1.5m and it’s been flowering for many weeks. The stems are stiff, the plants branch well, but setting them out 30cm apart proved to be too close as it’s tricky to extract the cut stems from the mass of branched growth without damaging them.

The flowers last well after cutting and make an ideal foamy foil to other flowers and these dainty daisies have a neat spiralled way of opening that repays close inspection in a bouquet. Cut flower growers should give it a try and it would also be good to try in prairie-style plantings.

The Flora of North America tells me that E. annuus is an annual, and it certainly looks like one. Its close relative E. strigosus is reckoned to be an annual or biennial or short-lived perennial. We shall see. I’ll be collecting some seed, and leaving some of it to self sow, and I’ll also be a leaving a few plants to see if they last the winter and re-emerge next spring. I really do suggest you give it a go.

* A month after the above picture, yesterday I took this one - still going strong...

Erigeron annuus
Erigeron annuus, still going srong a month after the first picture, in spite opf being cut for bouquets every few days.

Book Review: The Secret Lives of Garden Bees

SecretLivesOfGardenBees900

This week is Bees’ Needs Week, an annual event coordinated by the Department for Environment, Food & Rural Affairs and involving charities, businesses, conservation groups and academic institutions to raise awareness of bees and other pollinators. So what better time to remind you about this book?

I had no idea there were so many different kinds of bees! The Secret Life of Garden Bees by Jean Vernon (published by White Owl) really opened my eyes to the vast variety of these endearing and invaluable creatures. Two hundred and seventy six species in Britain alone.

Honeybees: yes, of course, I know about them. These are the ones everybody gets so worked up about. But they’re probably the ones least in need of protection - after all, there are beekeepers all over the country whose aim is to look after them. There are also the bees that burrow into the mortar in the front wall of my old stone house: yes, I know about them.

But I had no idea about, for example, the ivy bee which doesn’t emerge from its below ground nests until September when the first ivy starts to flower. Or Britain's rarest bee, the shrill carder bumblebee, known only from a few places scattered across southern Britain.

This is an eye-opening book and one thing that Jean Vernon does very well, as she guides us through a world that really is secret to most of us, is to present information that could be seen as off-puttingly technical in easy accessible language. It's crucial for writers aiming to engage readers with new and detailed material to carry them along, to present no barriers. Some resort to being superficial - but what's the point of that?

Reading The Secret Lives of Garden Bees we can absorb the information in an enjoyable way without feeling overwhelmed.

  • Declaration of interest: the author is a friend, and the book was supplied free of charge by the publisher.
  • A shorter version of this review appeared on Facebook in July 2020.

Trialling English Roses Old and New

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David Austin's English Rose James L. Austin (‘Auspike’)

The year 2018 marked the 35th anniversary of my growing David Austin’s English Roses. They sent me trial samples of Mary Rose (‘Ausmary’) and Graham Thomas (‘Ausmas’) back in 1983 and I’ve been a fan ever since, first visiting the nursery in the mid 1980s to interview David for an article and to see the breeding set up. I’ve often featured them in my work.

So I thought it would be good to mark the anniversary of the introduction of Mary Rose and Graham Thomas - still widely grown and highly popular - by growing them alongside the very latest David Austin English Rose introductions for that year and seeing how they compare.

So in April 2017, in my trial garden, I planted bare root plants of Mary Rose and Graham Thomas plus the three latest newcomers at the time - Dame Judi Dench (‘Ausquaker’), James L. Austin (‘Auspike’) and Vanessa Bell (‘Auseasel’).

You might think that planting bare root roses in April is rather late and you’d be right. But that’s when they arrived and they all grew away happily.

So, now’s the time to make an assessment. All are in same rich old cottage garden soil in the same open border amongst other shrubs and perennials and all have been treated in the same way.

The three newcomers have all made larger plants than the two oldies – clearly, this is good in some gardens and less good in others. I tried to prune them in a similar way and that’s how they’ve turned out. Here are my rankings (best to worst), for half a dozen features.

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David Austin's English Rose Graham Thomas (‘Ausmas’)

 

Beauty of individual flowers and clusters
James L. Austin
Graham Thomas
Dame Judi Dench
Mary Rose
Vanessa Bell

Impact from a distance
Vanessa Bell
James L. Austin
Mary Rose
Graham Thomas
Dame Judi Dench

Elegance of the maturing plant
Vanessa Bell
Mary Rose
James L. Austin
Graham Thomas
Dame Judi Dench

Appearance after a downpour
Graham Thomas
Dame Judi Dench
James L. Austin
Mary Rose
Vanessa Bell

General health
All very healthy. Only one patch of black spot, on one leaf, across all of them.

Fragrance (my sense of smell is fading, but…)
Mary Rose
Vanessa Bell
James L. Austin
Dame Judi Dench
Graham Thomas

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David Austin's English Rose Vanessa Bell (‘Auseasel’).

 

Individually
Dame Judi Dench Beautiful buds with red tips, small and nicely formed flowers but not enough of them. Throws up occasional long shoots. Fading petals drop off neatly.

Graham Thomas A lovely rich yellow shade, long flowering and dropping its faded petals reliably. Makes a rather inelegant plant.

James L. Austin Carries the largest flowers of the five, and beautifully formed, but developing white edges to the petals as they age and it holds on top its dead petals.

Mary Rose The neatest of them all, but still elegant, and with a strong old rose fragrance even I can smell.

Vanessa Bell Outstanding in the number of flowers per head, and the soft colouring, but full opening is delayed and it retains its faded petals spoiling the effect. But it has more or less no thorns.

So, on the basis of this mini-trial, are the three 2018 varieties better than the two 1983 varieties? Perhaps a little, but it depends what you’re looking for…

RoseMaryRose-IMG_0045-copy
David Austin's English Rose Mary Rose (‘Ausmary’)



My pick
I’d not grow Dame Judi Dench again but I’d be happy with all of the other four. But first of the five would have to be Vanessa Bell, with its prodigious flowering capacity, followed by James L. Austin for the size and individual beauty of the flowers.

British readers can check out David Austin Roses here.
American readers can check out David Austin Roses here.

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David Austin's English Rose Dame Judi Dench (‘Ausquaker’)

A new respect for elders

Sambucus 'Gate In Field' with dustbin lid ©EdBrown
Sambucus 'Gate In Field' with dustbin lid

Elders, Sambucus, have gone from infuriating me with their pigeon-pooped seeds popping up all over the garden –in a crack at the top of a stone wall, just out of reach, is a favourite spot - to being elite ornamental shrubs. British bred Sambucus nigra Black Lace (‘Eva’), with its reddish black, finely dissected foliage and its heads of pink flowers, must be the most popular new shrub introduction of the century.

I recently wrote a piece on developments in elders for the trade magazine Horticulture Week – subscription or free trial required – where I featured one of our top breeders, Ed Brown of Cotswold Garden Flowers.

I’d grown his ‘Chocolate Marzipan’ which is a spectacular plant growing 2-3m in a year, with huge chocolate brown leaves and huge marzipan-scented flowerheads. Huge is the word - one of the most amazing plants I’ve ever grown. I also came across one of Ed’s videos from the nursery (which now I can’t find) where he says that one of his varieties, ‘Gate In Field’, “has flowerheads the size of a dustbin lid and will grow to 14ft”.

Well, naturally, I wanted to see a flowerhead and a dustbin lid compared! So here we have it (above).

“My original aims as a breeder of Sambucus,” Ed told me, “were to breed better foliage and form and length of flowering season.

“But I have learnt that getting a new product into the commercial market takes years and new products fail for stupid reasons like space on a Danish trolley (the cart that delivers plants to garden centres). Gardeners are being deprived by all the garden centres: it all goes back to delivery week, transport, and a lack of knowledge or any willingness to take a risk.

“I tried waking the industry up ten years ago but after five years gave up and switched to colour, scent, flavour and length of flowering season.

“Sambucus has well tested antivirus properties,” Ed continued, “sambucol is sold in pharmacies to help the body fight infection. But it’s made from just one of the 147 named varieties in my Plant Heritage National Collection. It’s long overdue for the pharmaceutical industry to do more plant trials but, thanks to Brexit, the work that was being carried out between me and a Swiss company ended prematurely. So if there’s a masters student wanting work with National Collection holders, we’re here and waiting.”

Ed then gave me a few details about more of his best of his varieties.

‘Milk Chocolate’ “My first introduction, it has milk chocolate foliage and cream flowers and, given good soil, will flower until November.”

‘Milk Chocolate Orange’ “Milk chocolate leaves but with contrasting orange stems grows to 2m with all flowers presented on the top.”

‘Chocolate Marzipan’ (below) “Grows to 3m has amazing two tone foliage: black on top and mint green underneath, with almond scented flowers in June, July and August.”

‘Black Cherries’ “The darkest yet, it has the highest level of anthocyanin colour in the flowers and adds a cherry-like hint to cordial.1.5m high and very slow to reproduce needs to go into tissue culture.”

Find out more about Ed Brown’s Sambucus at Cotswold Garden Flowers.

Sambucus Chocolate Marzipan ©GrahamRice
Sambucus 'Chocolate Marzipan'

Lavatera is lost - but not Coleus

Malva (left) and Lavatera - both now Malva.
Malva (left) and Lavatera - both are now Malva.

The latest issue of the RHS magazine The Plant Review arrived recently – always a treat – and tucked away in what they call Classification Corner is the news that the genus Lavatera no longer exists – it’s been amalgamated into Malva.

Now most of us, taking a look at a Lavatera (above right) and at a Malva (above left), would wonder why they were separated in the first place. Needless to say, it’s all down to our old friend Carl Linnaeus, way back in 1753, and what Royal Horticultural Society botanist Dawn Edwards refers to as “differences in epicalyx segment fusion”.

Yes, but what on earth is the epicalyx? Well, the green calyx encloses the petals in bud, and the epicalyx refers to the little green bits that are outside the base of the calyx. Linnaeus thought that whether or not these little bits were fused together at the base (in Lavatera) or not fused at the base (as in Malva) was important.

It wasn’t long before botanists decided that Linnaeus had probably got it wrong but no one did anything about it until relatively recently. Back in 1998 molecular studies revealed that this division did not reflect the true relationship between the species grouped under Lavatera and those grouped under Malva. So, after careful deliberation – and they always deliberate long and hard these days, the RHS and botanists around the word agree - they’re all Malva.

I have to say: I can’t really disagree. And as they’re less separate than we thought, perhaps someone should try crossing them together…. Could be interesting.

• I should mention that it’s also been decided that Coleus are, indeed, Coleus. Not Solenostemon. Or Plectranthus. Which is good news all round.


Book Review: Peonies by Claire Austin

Peonies by Claire Austin
Peonies is the new book by Claire Austin

It’s peony season and we have a new book on peonies to savour. Written and photographed by renowned peony expert Claire Austin - her nursery lists more peony varieties than I could count – she doesn’t just describe her choice from the thousands of varieties she’s seen and grown over the years. No, she adds the fruits of her insight derived from decades of experience. (Well – enough decades to soak up the experience but not so many decades that… I’ll stop digging.)

The book is, basically, Claire’s choice of peonies, described and illustrated. We know we can trust her choice, and there’s no tricky botanical language in the text to trip us up. In fact I think that she sat on a stool in front of each variety and simply described what she saw. The best way.

But there’s more. So, apart from giving us the description of each plant we learn, for example:
‘Bunker Hill’ “Unlike many red lactiflora blooms, the petals don’t deteriorate quickly when the flower is cut.”
‘Emma Klehm’ “A useful plant for those who want a very late-flowering variety.”
‘Little Medicine Man” has flowers that are small “but produced in great numbers on stiff red stems”.
‘Marie Lemoine’ “Sadly, wet weather can spoil the flowers.”
‘Shirley Temple’ “blooms freely in a partly shaded spot”.’

She also notes, for each variety, whether or not it needs staking and the strength of its scent and lists more than two dozen varieties that she especially recommends for cutting.

Before we come to the descriptions and illustrations that make up most of the book, we have Claire’s advice on growing peonies, a summary of their development over the centuries, and a fascinating account of her own history with these everlastingly tempting perennials.

And I’m pleased to say that she slays the myth about moving peonies: “There is a long-held but totally unfounded gardening belief that peonies cannot be moved.” Got that? “unfounded”.

“Peonies have few ailments,” Claire continues. True enough. But a cut flower growing friend asked me just a couple of days ago why her white peonies were spoiling the purity of their colour with faint red flashes. I had no idea, so I hoped Claire’s book would help. But no luck.

So I’m very happy to have this book on my shelf, to enlighten me – and to steal from – whenever I need. Just one thing: the design is, well, a little bit dull. Modern plant books, including the excellent RHS Horticultural Monograph series and Discovering Dahlias that I reviewed here recently, inspire interest partly because of the elegance of their design. I see no designer is credited on this book. Claire should think about hiring a specialist designer next time.

  • An unimpeachable choice of the best varieties
  • Every variety illustrated
  • Descriptions based on personal experience
  • Thoughtful insight into each variety’s qualities
  • Readable and without reliance on botanical language
  • Design could be more stylish

“Dependable peony advice from our leading expert.”

Peonies by Claire Austin is published by White Hopton Publications at £25. Order a copy from Claire Austin’s Hardy Plants.

 

 


Physocarpus on trial

Physocarpus Midnight ('Jonight')
Physocarpus Midnight ('Jonight')

I’m a big fan of Physocarpus, ninebark as they’re known in North America from the way the bark repeatedly rolls back off the maturing stems. Though why it isn’t eightbark or tenbark I really don’t know.

These are hardy as rocks, deciduous shrubs grown for their colourful foliage, their clusters of white flowers, their autumn leaf colour and, to a lesser extent, their berries.

The first to come to our attention in modern times were ‘Diablo’, with dark purple leaves, and ‘Dart’s Gold’, with bright yellow foliage – both useful shrubs. But it was when these two were crossed together to create what is known as Coppertina in North America and Diablo D’Or in Europe (its raiser’s name is ‘Mindia’) that I really started to take notice.

I was sent trial plants of this by Proven Winners, the American plant marketing company, now expanding into Europe, and year after year it was a star in my Pennsylvania garden for its foliage that opens in amber yellow and matures through orange to purple-bronze.

More recently I planted some that I didn’t know so well on my trial garden in Northamptonshire - thanks to John and Maria Jones of Hyfryd Plants in Wales for help with sourcing plants - and it’s time for a report.

But before that, I just want to mention physocarpus for cutting. America’s Association of Specialty Cut Flower Growers has twice voted a physocarpus as its Cut Flower of the Year. And although it can be good to cut branches lined with flower clusters, Firebrand (below) looks ideal for that use, of those I’ve tried Midnight (top) is the best and holds its leaves well as they turn.

I find fruiting unpredictable and tough to assess because those that carry the most flowers are the ones whose flowering sprays are cut for the house. The quality of autumn leaf colour, too, seems unpredictable.

New physocarpus varieties are still being released. Two dozen are listed in the current RHS Plant Finder and we’re awaiting the results of the trial of thirty varieties at the RHS Garden at Wisley that ended in 2019. In the meantime, here are my thoughts on my own mini-trial.

All Red (‘Minalco’)
I was especially looking forward to seeing All Red mature as it was touted as being smaller, more bushy, more compact and with red-bronze foliage that was noticeably smaller than that of other varieties. That’s all true - except that after a couple of years it started to produce a succession tall, very vigorous, large-leafed shoots , with internodes more than twice as long as on All Red itself. They emerged low on the plant and would have taken over completely had I not cut them out. This one is going on the compost. Now rarely seen, rightly. Bred by Pépinières Minier in France.

Firebrand (‘Hyfbrand’)
The foliage is coppery orange in the shoot tips, maturing to dusky purple bronze with green undersides. The flower clusters, spread across 30-40cm of stem, are relatively small, but produced on short stems at every node creating a very attractive look. Pink buds open to pink-tinted white flowers, it retains more pink colouring in its flowers than others I’m growing. Bred by John and Maria Jones of Hyfryd Plants in Wales.

Lady in Red (‘Tuilad’)
Reddish copper young shoots mature to dusky greenish purple foliage, the small clusters of pink buds fade to white as the flowers open. This is similar to Coppertina, which is said to be mildew resistant although I’ve not had powdery mildew on any of mine. This can stay in its up-against-the-east-facing-fence site until I’m desperate for space, but if I were planting now I think I’d pick Coppertina. From Jonathan Tuite of Westacre Gardens in Norfolk.

Midnight (‘Jonight’) (above)
If you’re looking for the darkest foliage colour, this is the one. The leaves open in deep purple-bronze foliage with a noticeable gloss, maturing to dull bronze - almost black- and greenish bronze on the back. The vigorous growth is ideal for cutting and lasts exceptionally well. Not selected for its flowers, so the show is sparse but the rosy pink buds open to white flowers. Another from John and Maria .

Summer Moon (‘Tuimon’) (below)
More spreading in growth than my other varieties, the chartreuse-bronze new growth matures to green with pale veins and hints of bronze creating on overall blend of green and bronze tints. The flower clusters are larger than those on any of the others, and on longer stems, with the pink buds opening to white and with noticeably red anthers. Makes an effective flowering shrub, wider than high. Another from Jonathan Tuite.

Check out my previous posts about growing physocarpus in Pennsylvania.
New plants on trial: Top Shrub – Physocarpus Coppertina (2007)
Two fine Physocarpus (Ninebarks to American readers) (2009)

PhysocarpusSummerMoon-_G036970
Physocarpus Summer Moon ('Tuimon')

Flowers from your local flower farm

Flower and Farm bouquet with sweet peas and Iceland poppies
It’s becoming a big thing. Grow local. Whether it’s Brexit causing problems for nurseries moving plants into and out of Britain or the madness of flying cut roses half way round the world, everyone with half a brain can see that buying plants and flowers and food locally instead of from hundreds or even thousands of miles away makes sense. And don’t talk to me about sending beef to and from Australia…

Flowers From The Farm is a membership association promoting artisan growers of seasonal, sustainable British cut flowers Established only in 2011, Flowers From The Farm now has over a thousand growers and florists exchanging ideas and advice. Their Find Flowers facility is the place to start looking for local flowers whether you’d like to give a locally grown bouquet, or buy for yourself, or you need local flowers for your business.
This spring I’ve been visiting some of the Flowers From The Farm members and a couple of days ago I called in at Flower and Farmer in gentle hills of west Northamptonshire. (For North American readers: this is pretty much in the middle of England.)

Started only in 2018 by aunt and niece team of Jo de Nobriga and Milly Naden-Robinson, Flower and Farmer have one and a half acres of flowers and foliage to supply wholesale to florists and floral designers, for weddings and events, and for sale at regular the farm gate openings. They're now on their way to doubling in size.

Growing flowers for cutting is very different from growing flowers in garden borders and although bursting with horticultural experience, Jo and Milly have had to learn new ways of growing, especially under cover – and learn fast. And they have. Jo, in particular, is ruthlessly self-critical but the result is a sharp attention to detail. Consider the refreshments.

They kindly offered us tea. Ordinary or Earl Grey? How strong, first pour? Cake? Lemon drizzle or chocolate fudge? Corner slice or side slice? Getting the tea and cake right for their visitors was important and it’s the same with the flowers.

They’re delighted with what they’ve achieved – but are always looking to improve, looking for new varieties and thinking about efficient sustainable ways of growing. The autumn-sown ‘Spring Sunshine’ sweet peas in the tunnel looked excellent – with 18in/45cm stems – but right at the front was one stem that had dropped its buds. What could they do about that? There were not enough Iceland poppy plants in pastel and peachy shades and too many primary colours. They’re looking into that too. Paying thoughtful attention to the flowers is the way to maintain high standards - and the way to improve.

I can’t wait to go back… Their next farm gate sales days are Saturday, 12 June and Saturday, 17 July (11am – 2pm). You can collect pre-ordered bouquets, and flowers are sold by the individual stem so you can choose exactly what you want. PLUS there are teas and homemade cakes whose quality I can enthusiastically endorse! Corner slice or side slice?

Find out more about Flower and Farmer at https://www.flowerandfarmer.com/
Follow Flower and Farmer on Facebook
Follow Flower and Farmer on Instagram

And if you’re too far away, check the Find Flowers facility on the Flowers From The Farm website to discover your local flower grower.

 


Discovering Dahlias

Discovering Dahlias by Erin Benzakein
Having been despised as garish and – frankly - the flowers of the lower classes for decades, the rehabilitation of the dahlia began with the very definitely not-at-all working class Christopher Lloyd using them extensively in his garden at Great Dixter, in Sussex.

The dahlia has never looked back and the books have followed. There are three more recent and upcoming dahlia books that I’m going to discuss here over the coming weeks and the first is Floret Farm's Discovering Dahlias by Erin Benzakein.

I’m a big fan of Erin Benzakein. She runs Floret Farm in Washington State and has done more than most to popularise the idea of locally grown, non-industrial cut flowers. She’s gone from a one-woman enterprise to planting twenty acres in just a few years.

I really enjoyed her first book, Floret Farm’s Cut Flower Garden, and reviewed it here in 2017, and now comes another.

This is an inspiring book, but not without its faults. The photography, by Erin’s husband Chris, is immediately striking not just for the awe inspiring views of the cutting fields but for the delightful detail revealed in the close-ups.

The catalogue of Erin’s recommended varieties is arranged by colour and there are, for example, five pages of dahlias in peachy shades – thirty varieties in all – and all shown in huge bunches held by Erin in front of her ubiquitous blue shirt and described in detail. It’s all so tempting that wants lists soon extend to a second page of back-of-the-envelope scribble. And this where things begin to become less convenient.

There’s no list of suppliers of dahlia tubers and/or cuttings in the book. Instead, we’re directed to the Floret Farm website where we must sign up to receive the “Discovering Dahlias Bonus Materials” by email. A great way to collect email addresses. This arrives promptly and includes descriptive details (not just a name and a link) of twenty three American dahlia specialists, seven in Canada, four in mainland Europe - but only two from the UK. Not good.

Three hundred and sixty varieties are included in the directory. I presume they’re all available from American suppliers – frankly, I just don’t have time to check. But I looked up all those peachy varieties in the latest edition of the RHS Plant Finder – which lists all the plants available from British and Irish nurseries, 81,000 of them. Eight of the peach varieties are listed with at least one supplier – twenty two are not listed at all. And if you want to check Erin’s thoughts on varieties you already have on your wants list – forget it: there’s no variety index.

The practicalities are very much based on experience in Washington State and British growers, and growers in other parts of North America, will need to adapt. She assumes you’ll root your cuttings under lights, for example.

So we end up being inspired and tempted and mad keen to add to our dahlia collection – or start one. American readers can, I assume, spark their enthusiasm into action. British and Irish enthusiasts will have quite a lot of work to do.

  • Beautiful and inspiring
  • A tempting choice of varieties revealed
  • Paper and print quality excellent
  • Extremely well priced
  • Few recommended varieties available in Britain
  • Skimpy pest and disease coverage
  • Sad absence of a variety index

“Beautiful to look at and genuinely inspiring, but it could do more to help turn inspiration into achievement.”

Floret Farm's Discovering Dahlias by Erin Benzakein is published by Chronicle Books.

Order Floret Farm's Discovering Dahlias in the UK

Order Floret Farm's Discovering Dahlias in North America

 

Discovering Dahlias by Erin Benzakein - the first peachy pages


They're all foxgloves, Digitalis - OK?

Digitalis x valinii (centre) and its parents-©GrahamRice-©T&M-©ScottZona

“The smartness and absurdity of plant names” is one of things I’m going to be discussing here on the re-launched Grahams Garden blog, as I did on its predecessor Transatlantic Gardener. We can start with an old favourite given heightened absurdity by the good people at the Royal Horticultural Society – Digiplexis.

“Oh, no!” I hear you cry… Yes, I’m sorry. And we’re going to do Mangave as well…

So. Here’s the story.

Our British native foxglove, a familiar tough biennial, is Digitalis purpurea (above left). The Canary Island foxglove is Digitalis canariensis (above right), a tender rather woody perennial. Charles Valin, then plant breeder at Thompson & Morgan, crossed the two species together and gave the resulting plant the name of Illumination Pink (above, centre). It won the Chelsea Flower Show Plant Of The Year award in 2012.

But, before the Canary Island foxglove was Digitalis canariensis, it had been Isoplexis canariensis – botanists had thought it was sufficiently different from other foxgloves to be in a genus all of its own. Closer examination proved that this was a mistake and the fact that it crossed easily with D. purpurea was one of the reasons that it was re-classified as a Digitalis. The RHS botanists gave the new hybrid the botanical name of D. x valinii, commemorating the breeder who first made the cross.

Other breeders then got in on the act and made their own crosses. And, somewhere along the way, over in the United States, someone decided that crossing two different genera together – Digitalis and Isoplexis – sounded much more impressive than crossing together two different Digitalis and the name Digiplexis® was born. This was much more a marketing exercise than it was a piece of thoughtful botanical nomenclature.

So, let’s be clear. Digiplexis® is an invalid, made up name with no standing whatsoever and which only serves to confuse gardeners. So it was especially maddening to see, just the other day, in the new plant centre at the RHS Garden at Wisley in Surrey, plants labelled Digiplexis® (below). And note the little symbol for a Registered Trade mark. This is a marketing exercise, not a plant name. Aren’t plant names confusing enough, without this sort of nonsense - and without one branch of the RHS muddling up the good sense of another?

But wait, there’s more. Pretty much the same thing has happened with Mangave®. Note that little ® again. This time we’re talking about rosette-forming succulents mainly from arid regions of the Americas – Agave and Manfreda. Nearly twenty years ago it was recognised that there was no justification for keeping these two genera separate so Manfreda was merged into Agave. All very sensible.

But then in the same way as with those foxgloves someone realised that, from a marketing point of view, crossing plants from two different genera was much more impressive than crossing two different species of the same genus. And Mangave® was born, recommended for patio planters.

But there’s payback for this sleight of hand. That first Digitalis hybrid turned out to be far less hardy than was originally announced and so the name Digiplexis® has become attached to plants that fail to make it through their first winter. Something similar will probably happen with Mangave®, which in the UK needs grittier compost and more winter protection than is often mentioned.

But haven’t we suffered enough? In recent years plant taxonomists have taken on board the idea that they exercise caution in their decisions about plant names and respect the needs of the wider plant community. The shoot-in-foot madness of trying to make us call chrysanthemums Dendranthema is long gone.

But then someone else comes along and confuses everyone all over again. And the very least that the RHS can do is make sure that it agrees with itself.

Digitalis x valinii on sale as Digitplexis at the RHS Plant Centre at Wisley