A couple of weeks ago I was telling you about ‘Fenway Park’, the lovely yellow leaved form of the Boston Ivy, Parthenocissus tricuspidata, and how it was found as a sport on a plant growing on a building near the Fenway Park stadium in Boston.

Well, regular Transatlantic Plantsman follower Ron Rabideau of Rare Find Nursery in Jackson, NJ has done us all a great favor by sending me a picture of the original plant, as first discovered on that old apartment block near the stadium. And here it is.

The picture was taken by Peter del Tredici, who first spotted the plant on the way to the ball game and made sure it was propagated. Unfortunately the plant is now gone.

Isn’t it great to see a fine new variety at the moment of discovery? Thank you Peter and thank you Rob (and Anne at Rare Find for telling me the picture even existed).

And you can check out the original post about Parthenocissus tricuspidata ‘Fenway Park’ here. In that post I mentioned Plant Delights nursery as a source - they’re now sold out.

But Parthenocissus tricuspidata ‘Fenway Park’ is available by mail order from Rare Find Nursery.

My last post was prompted by an article from the latest issue of The American Gardener, the members' magazine of the American Horticultural Society.

What I saved for this separate post was the news that The American Gardener has gone digital. It's now available in a lovely digital turn-the-page-on-the-screen format - and it looks amazing (left, click to enlarge the first page). You can turn the pages, search it, zoom in to individual pages - scale it up to full screen size and it still looks great. There's even an interactive Osmocote ad. And, I might say, it's a step ahead of its venerable equivalent in Britain - no sign of the Royal Horticultural Society magazine The Garden going digital.

The first digital issue of The American Gardener is available free to anyone who cares to take a look - and you should. From the next issue it will only be available to AHS members - seems fair enough, they're the ones who pay their subscription after all. You can join the AHS here.

Just before I flew back to Pennsylvania I took in the spectacular trials at BallColegrave near Banbury in Oxfordshire. BallColegrave is the British arm of Ball Horticulture and supplies seed and plugs to professional growers.

Since Darwin Perennials has joined the Ball Horticulture group, the BallColegrave trials have broadened out from their previous colourful emphasis on flowering and foliage annuals and now also include a good range of perennials.

Actually, to be honest, it’s all more of a display than a trial and the main feature is the chance to see a huge range of plants maturing in containers – just way we grow them in our gardens.

It was impressive to see billowing baskets of petunias and begonias - including the new yellow Million Kisses Honeymoon and the award winning ‘Glowing Embers’ as well as some impressive new coleus like ‘Dark Chocolate’ in green with a chocolate flash at the base of each leaf. And the startling Impatiens ‘Masquerade’ (top, click to enlarge) stood as it does wherever it’s seen.

Amongst the perennials it was good to see heucheras, like ‘Brownies’ (right, click to enlarge), in large tubs as well as huge tubs of astilbe and phlox.

I was able to call in before the first open day, so they were still setting up and it was raining and blowing a gale – so no dramatic views, I’m afraid, although here’s one from the air ten years ago (left, click to enlarge) – plenty of colour!

But don’t take my word for it – go yourself. It’s free. BallColegrave’s open days for the trade are continuing until 6 August, they have an open day for the gardening public in a couple of days time, and there’s also a Customer Day for American growers in Chicago on Friday.

I have to say, however, that the information on the British event is a little hard to find on Ball’s not-very-user-friendly website. Follow the link for the British Trade Open Days and unless you’ve previously been on the site and selected United Kingdom in the Select Your Country menu – it just doesn’t work. The whole site is infuriating. Hit the New Varieties link on the UK site… nothing. They’ve taken the page away! And just when they're showing off their new varieties... Sigh...

Well, they may not be able to build a user-friendly website but they can certainly create some impressive new plants – and show them off well too.

BallColegrave Trade Open Days continue until 6 August, every weekday 9am-5pm
Ring 01295 814 702 if you can’t find it on the website.

BallColegrave's Public Open Day is on on 30 July, 4-8pm.
More or less no details on the website, ring 01295 814 702

Ball Horticulture Customer Day in Chicago is  at the Gardens at Ball, West Chicago, Ill on 30 July, starting at 8am. This even has its own microsite - excellent.

There’s a great overview of sunflowers in the latest issue of The American Gardener, the membership magazine from the American Horticultural Society. It covers annual and perennial sunflowers but one of the pictures leapt out off the page.

The tall stems of Helianthus maximiliani ‘Santa Fe’, lined with bright yellow daisies look amazing (left, click to enlarge). In particular, I immediately thought this plant would make a superb cut flower.

I vaguely remembered that I’d included the species in my Encyclopedia of Perennials – and there it is. And I find that the daisies expert who helped with the Helianthus entry gives its height as 10ft/3m! (Always wise to start by looking things up in your own books, that's what I say.)

So I next took a look at the “bible” on less familiar cut flowers - Specialty Cut Flowers by Allan Armitage and Judy Lauschman. And to be honest the small entry was not very encouraging. “The very tall plants (up to 9ft, 3m) can be used to lengthen the season. They… can be invasive.”  See what I mean? Not exactly a vote of confidence. And at 9or10ft/3m, that is one hell of a cut flower – what am I supposed to arrange it in, a pond?

The American Gardener article illustrates ‘Santa Fe’ but doesn’t actually say how it differs from the usual species. So I had a look online.

High Country Gardens sell it and they say that ‘Santa Fe’ “is our superior cultivar selected for its incredible flowers, stunning foliage and mid-fall bloom time”. So I’ve happily arrived at the nursery who raised it! And they’re based in, need you ask, in Santa Fe, New Mexico.

You’ll notice that their picture (left, click to enlarge) shows a rather shorter plant with spectacular stems crowded with flowers.I think I’m going to order ‘Santa Fe’, and the two other forms they list, and see how they all do here at the opposite end of the country.

I see from the USDA website that Helianthus maximiliani grows all over the country – including our corner of north east PA, though I've never seen it round here. And the High Country Gardens website says it’s hardy to zone 4 – that would be -34C (-30F)! Can’t wait.

And since I started working on this piece a couple of days ago – it’s gone on sale! I’d better get my order in.

Back in March, I posted a piece here titled New US hardiness zone map launches soon!! Well, it hasn't launched yet, I'm sad to say, but in the current issue of the RHS magazine The Plantsman there are two articles which explore the whole issue of hardiness and hardiness ratings in more detail.

The first is by Scottish plantsman and rhododendron guru Kenneth Cox entitled Evaluating Plant Hardiness. The second is by me and is entitled An International Perspective on Hardiness Ratings. Click each title and the article will appear in a new window

As our climate continues to change, as horticulture becomes more internationally connected, and as gardeners become ever more eager to stretch the limits of what they grow, plant hardiness and how to make clear to gardeners which plants are hardy in which areas becomes an ever more important issue. These two articles make an interesting contribution to the continuing debate.

Plants are discovered, and come by their names, in some intriguing ways…

One day in 1988 Peter Del Tredici of the Arnold Arboretum in Boston Massachusetts was walking to a sports game. He was on his way to Fenway Park to watch the Boston Red Sox (For Brits: They’re a big baseball team. Baseball? You know about baseball? OK.).

The dramatic self-clinging climber Parthenocissus tricuspidata grows on so many buildings in Boston that it’s long been known as Boston Ivy. As he walked to the stadium he noticed that there was a yellow-leaved shoot on a plant climbing up an apartment building. He begged some material to propagate and so when the plant was introduced it was called Parthenocissus tricuspidata ‘Fenway Park’.

It’s an impressive plant. The leaves open bright yellow and in a sunny situation they retain their color. In shade, the leaves tend become a limey green color. In the autumn the leaves develop fiery red, orange and yellow tones.

It just takes a moment and a good eye to spot a great new plant - and to give it an appropriate name. Now if only we had a picture of the yellow shoot on the plant on the building...

Parthenocissus tricuspidata ‘Fenway Park’ is available from Plant Delights Nursery (though their story is slightly different.) In Britain it’s also available from these RHS Plant Finder nurseries.

I was astonished recently to discover that the British edition of my Encyclopedia of Perennials had been translated into both French and German (click the image to see the jackets)! The publishers had somehow omitted to pass on this information, although there’s an indication buried deep in the royalty statement where, I confess, I usually fail to look. With the American, British and also the Canadian editions of the book, that makes five in all.

It's great that all that work , and some much information, is finding its way around the world.

Order the French edition of my Enyclopedia of Perennials
Order the German edition of my Enyclopedia of Perennials

For the last few days I’ve been buzzing round Britain’s Hampton Court Palace Flower Show, the largest flower show in the world, where I’ve been reporting on various plant related issues.

It’s a wonderful show, with impressive outdoor show gardens and some of the most impressive floral exhibits seen at the Show. The show runs until Sunday and tickets are still available. And I have to say that one of the highlights is a spectacular vegetable and fruit garden.

But here are a few links to my reporting…

New Roses – with the focus on disease resistance
New Flowers – climbers, perennials and annuals
New Food Plants – fruit, veg and herbs (Coming soon)
Planting Combinations  – harmonious planting schemes
Foodie Planting Combinations – attractive plantings of ornamental food plants
Perennials – interesting plantings from around the show

You can access them all from here

And also coming soon is a short video interview featuring some of the most interesting new plants at the Show.

It's a great show, whether you're most interested in plants, gardens or all the ancillary paraphernalia. I came away with a lovely plant of Clematis Reflections™ (‘Evipo035’), raised by Raymond Evison and sold at the show by Taylor's Clematis Nursery, and four crocosmias in softer shades from Trecanna Nursery. I'll be trialling them as possible cut flowers.

I’ve been thinking about plants for dry shade, recently, and hostas in particular.

Now - no one would suggest that hostas positively adore conditions which are both dry and shady but, like so many plants for dry shade, it’s more that some will do well there – even if they’ll do even better somewhere else.

I’ve been looking around for a while, and taking notes on the issue, then I started to wonder which features in hostas would make some more suited to the conditions than others.

Long ago I planted that old old favorite Hosta lancifolia in dry shade, its shining green leaves overlapping like fish scales, and fifteen years later it was still doing well. I’ve noticed that another old favorite, H. sieboldiana var. elegans, with broad blue leaves of heavy substance, also takes the conditions well.

Those most likely to fail, it seemed to me, would be those with broad white variegations. In difficult conditions plants need as much chlorophyll as possible, and those with wide variegations at the edges where the leaf tissue is thinnest would also be most likely to suffer under stress.

I read the works of experts and found that 'Albo-marginata', ‘Ground Master’ and the rarely seen H. kikutii var. yakusimensis were recommended. But then I thought I ought to ask some people who really know their hostas. So I asked two experts: Diana Grenfell, author of some excellent books on hostas and a holder of the British National Collection of miniature hostas; and Ian Scroggy, who runs Bali-Hai Nursery in Northern Ireland, and who sells to both the UK and the US. Both gave me their thoughts:

Diana Grenfell said: “Hosta lancifolia grows in great drifts in the Savill Gardens at Windsor in inhospitable conditions as do 'Crispula' and, if I remember correctly, 'Decorata'. I am told that  'Blue Angel' will tolerate dry shade but will only attain leaves half their normal size;  obviously in a small garden where they can be watered and well fed they will perform better. 

“Some of the old fortunei types with thicker leaves like 'Rugosa' and 'Hyacinthina' may also tolerate dry shade.” I have to say that Diana was much more in favor of not subjecting hostas to dry shade at all!

Ian Scroggy told me: “Any of the Hosta tokudama plants and cultivars are ideal, in drier shady areas the color comes out much better. All of the tokudama plants are very slow to grow so do not require as much moisture in early spring to come into leaf. They are always nearly the last hostas to come into leaf but hold their leaves much longer into October.

“Other Hostas would be the siebioldiana types; they produce very woody root systems which again really hold moisture in their roots and release it slowly to the plant.  In dry shade H. sieboldiana ‘Elegans’ will put on extra "bloom" or wax onto its leaves and really looks like someone sprinkled blue powder dust all over the leaves.”

Two interesting aspects to those thoughts from Ian Scroggy. One: slow growing is good, because if plants grow slowly they need less moisture. Two: woody root systems are good for moisture storage.

Fascinating. Thank you Diana and Ian. Now I just need to ask someone about daylilies for dry shade…