Transatlantic Plantsman

The variable mayapple

Taking a look at the flowers not yet overwhelmed by Japanese knotweed along the Delaware River in New York yesterday, I found some interesting mayapples (Podophyllum peltatum).

With its pairs of umbrella-like leaves and single flowers hanging between, this is a familiar American woodlander often occurring in broad sweeps in deciduous woods. It’s very distinctive.

In these woods along the river, there was a great variety of leaf shapes and colors – at various stages of development – just a few yards apart. In the first picture, a patch of well developed green foliage represent the familiar type. The second picture, taken about 10ft from the first, shows a late developer with bronze tinted foliage. On another site a few miles away, the distinction between early green and late bronze was even more apparent.

A pretty pink-flowered form with bronze-tinted leaves is occasionally listed by nurseries, that’s the one in the third picture – not quite flowering in the garden here.

I’ll be checking he flowers on all of them soon.

BTW – Research has shown that germination of mayapple seed is improved if the fruits are eaten by, and pass through, a box turtle!

Sanguinaria - the spring overture

The Canadian bloodroot, Sanguinaria canadensis, is one of those fleeting spring flowers which is such a joy when it’s out but no sooner has its six- to twelve- petaled white flowers, the inner slightly broader than the outer ones,  been enthusiastically admired - than the petals drop. Fortunately, it has bold foliage for months after so continues to catch our attention.

The fully double form, f. multiplex, is a stunner with all its stamens transformed into petals to make a more impressive, though less delicate, display which also lasts a few days longer. And yes, the correct name for this fully double form is, simply, f. multiplex. The flowers seem to vary in size a little as the plant ages – it seems a good idea to lift, split and replant in good soil every few years.

Here, this is a vigorous plant and has increased from five or six flowers in its first year to about 30 flowers this year, two years on. Tony Avent at Plant Delights reports this form flowering much later than the wild form – not here.

I also grow a semi-double form with 12-16 petals, the outer noticeably broader than the inner, which came from Darrel Probst’s GardenVision nursery under the name of “Tennessee Form” but which seems to be a good match for the correct ‘Flore Pleno’ (aka ‘Plena’). Linc Foster, in his book Cuttings from a Rock Garden, explains in impressive detail why f. multiplex is the correct name for the familiar fully double form while ‘Flore Pleno’ is the correct name for the form with 14-16 petals.

Also from Garden Vision came “Pink Form”. Interestingly, the Garden Vision catalog describes it as opening light pink and fading to shell pink. My plant, has 12-14 petals whose inner surface is white, with perhaps the faintest blush, while the backs are pink with pale veins. The leaf stalks are slightly more pink tinted than the usual form but the plant seems altogether less pink that the catalog description implies. It’s also a slow developer but is lovely in the evening when the petals close and the pink coloring is revealed.

Other names that are occasionally seen are: ‘Paint Creek Double’, a semi-double form with very slender petals (more pictures here); ‘Betty Casto’, which looks very similar, I’m still trying to find out what the difference is supposed to be - and I wonder where Paint Creek is; ‘Peter Harrison’, which looks like my pink form; ‘Amy’ and ‘Rosea’ are also pink but it’s unclear how (or if) these pink forms differ.

This lovely plant is like an overture to the spring here in PA, and as the petals drop hellebores are at their best and epimediums and wood anemones and the first trillums and the various Lathyrus vernus and the rest are all coming into their own. Lots to see, now.

Been waiting years for this bear picture!

When we first came to Pennsylvania, I read somewhere that the emerging skunk cabbage (Symplocarpus foetidus) was a favorite food of black bears when they first come out of hibernation in spring. I’d found plenty of mangled plants (see below) but never actually seen a bear feasting.

Finally, here’s a picture of a black bear actually eating skunk cabbage by the little creek alongside our garden. Thank you judy.

Her two cubs (not much bigger than our cats) were scampering around, not really paying much attention, the way kids do, while she munched on the emerging foliage. In the past I’ve seen plants pulled up and the fat roots eaten but this bear concentrated on the emerging unrolling leaves – it’s like she bit the heart out of a cabbage.

Our streamside display of “the American hosta” is going to be a little ragged this summer – but who cares! It was a treat to see – from a distance, with a long lens, of course.

You may have noticed I've posted about skunk cabbage before - here, and here.

The extraordinary skunk cabbage

"The skunk cabbage, Symplocarpus foetidus, is one of the most curious and widespread wild flowers of the midwest and northeast. Its disparaging common name tends to devalue a fascinating flower which, while certainly not a horticultural marvel, is sometimes cheekily referred to as the American hosta – especially for the benefit of overseas visitors. But what makes this relatively demure flower so intriguing?"

So starts my piece on this fascinating plant in in the January-February issue of American Gardener magazine. Members of the American Horticultural Society can read the piece here. If you're not a member, I urge you to join.

There's more on this plant from last April here on Transatlantic Plantsman. Read it here.

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.

British and American hollies

Back in England… I hear that the frost has finally reduced to a squishy mess those impatiens back in Pennsylvania that had been protected with old bedsheets. It’s now just too cold… The lady’s tresses orchid was still looking good when I left a couple of days ago and is a little more resilient in the face of yesterday’s snow.

First stop here was the Royal Horticultural Society show where the society itself staged an exhibit of hollies. Most of the plants on this fascinating exhibit came from the Society’s west of England garden at Rosemoor in Devon. Curator Chris Bailes, author of the recent holly monograph – perhaps the best plant monograph of the last year – told me that recently flocks of fieldfares and other birds had begun to strip the plants of berries. But there was still plenty to see on the exhibit. [Fieldfares are related to British blackbirds, and the American robin.]

It was especially interesting for British visitors to see the deciduous American Ilex verticillata (first picture), its stems crowded with berries, alongside the more familiar evergreen I. aquifolium and I. x altaclarensis.

Chris also pointed out to me the value of a circular exhibit at flower shows, in preference to rectangular or square stands. He says that visitors tend to follow their way all the way round a circular exhibit but when they arrive at the corner of a rectangular stand they tend to keep walking across the isle to the next display. You learn all sorts of fascinating things at these show…

A gorgeous pink perennial lobelia

A few weeks ago I mentioned the startlingly scarlet Lobelia cardinalis (cardinal flower) growing by our little stream. Well in the garden there’s lovely wild variant. As you can see it’s a soft rose pink, shading to white at the base of the petals, the flowers opening from coral pink buds.

This came to me from Georgia native plant wizard Don Jacobs, whom I’ve mentioned here before. He’s spent decades searching out natural variants of native plants and this is a real treat.

Growing in soil which is less damp and less rich than is ideal it’s steadily getting stronger and is still has a few final flowers here at the end of October. It will be interesting to see if the bees take pollen across to those wild ones fifty yards away. I’ve made a point of not growing the sophisticated hybrids bred in Germany – the Compliment and Fan series – superb though they are as I didn’t want the wild ones to be contaminated. Rightly or wrongly, if pinks turn up by the stream I don’t think I’ll mind at all.

One of the big wholesale growers now has 'Eco Pink Flare' in production, so look ouit for it in nurseries and with mail order suppliers next year.

Perennial for fall color

Well, as the trees are just passing their full fall splendor here in north east PA it’s easy to forget that fall foliage color is also a feature of some excellent perennials. One of the best for fall color is one of the bluestars, a US native from just two states (Oklahoma and Arkansas), Amsonia hubrichtii.

Its common name comes from its summer starry blue flowers, rather like those of the Vinca (periwinkle) to which it’s related. But its chief glory is about now when the whole mass of slender foliage turns bright and buttery yellow. With Physocarpus ‘Coppertina’, which looks to be the best of many recent new shrub introductions and whose foliage turns bronzy purple in the fall, the amsonia would make a great picture. Add a ruby, rusty or coppery Korean chrysanthemum like ‘Ruby Raynor’ or ‘Lucy Simpson’ or ‘Paul Boissier’ and you’ll have a combination that’s more than a match for the fall lcolor in the trees all around.

Fine fall orchid – for zone 4

The fall foliage may be the most spectacular feature of both the garden and landscape at this time of year, but outside my window here in PA a little treasure is in full flower.

The nodding lady’s tresses, Spiranthes cernua, is a native orchid that grows across a wide range of the US, from the eastern seaboard across to Texas, Kansas and Nebraska. I didn’t dig mine up from the wild, I should say, it came from native plant specialist Don Jacobs of Decatur, GA.

This year it’s noticeably taller than last, about 18in/45cm as against about 12in/30 in its first season last year. I have to say I gave it a dose or two of MiracleGro during the summer which I wouldn’t do for with most orchids! The white flowers are clustered towards the top of the stem – the picture covers about 2in/5cm and shows the spiral arrangement of the flowers. In the wild it grows in damp places – fields, meadows, along streambanks and lakesides as well as in roadside ditches. You can see more pictures on the USDA plants website.

The unusually vigorous and fragrant cultivar ‘Chadd’s Ford’ was found in a Delaware ditch and you can buy it from Sunlight Gardens.  In fact the native fragrant form, from the south, is sometimes distinguished as var. odorata - you can order it from Plant Delights.

This is one of the easiest of all orchids to grow out in the garden – otherwise it wouldn’t be thriving in the terrible soil we have here – and it’s hardy too, down to zone 4. And it seems to like MiracleGro!

Witch hazel – flowers and foliage

It’s that time of year when the scent of the witch hazel begins to waft through the woods. True, the fragrance of the American native witch hazel, Hamamelis virginiana, doesn’t have the penetration of the spring flowering Asian species but it’s a treat to catch its sharp sweetness on the way to mailbox in the morning.

This year it seems especially prolific – and it’s also opening while the foliage is still green and still on the plants. So unless you knew, you’d be wondering where the scent was coming from as the flowers are almost completely hidden. The flowers usually appear on bare branches, and the presence of the leaves disguises the fact that when you see a whole group of plants… well, it’s the usual thing with so many natives in the wild: the plants vary, in this case in the flowers vary in color, in length of petals and in exactly when they open (some are earlier than others).

At the same time, the foliage of the familiar hybrid of two Asian species, H. x intermedia ‘Mollis’, is just starting to color up in the garden. No flowers till spring, and a much more pervasive scent, but soon it will be covered in beautiful buttery and gold leaves.