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

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)

Physocarpus Summer Moon ('Tuimon')

The tall and colorful American native summer phlox, Phlox paniculata, has been popular for more than a hundred years. In 1917 five hundred and eighty four (yes, 584) different varieties were grown in the USA and in 1907 one Scottish nursery alone listed well over three hundred varieties. In Britain, the Royal Horticultural Society currently has a grand total of 577 in its database.

Most of these have now vanished, but there are a number of impressive breeding programmes, many using other species in addition to P. paniculata, going on in both North America and in Europe. Hans Hansen at Walters Gardens in Michigan, with his Opening Act and Fashionably Early series, and Charles Oliver at The Primrose Path in Pennsylvania, with his Earlibeauty Series (above), are leading the way along with Gosen Bartels in The Netherlands with his Flame Series.

But some of the best known varieties of the summer phlox have arisen in another way – they’ve been spotted in the wild or in abandoned gardens by plants people with a good eye, and an appreciation of something special.

I’ve mentioned these in my article about phlox in the current issue of The American Gardener but space was tight so I thought you’d be interested in a little more detail. These were all chosen for their freedom from mildew, but it’s important to remember that mildew resistance is not constant. I’ve seen ‘David’, and ‘David’s Lavender’, completely ruined by mildew.

‘Common Purple’ Found in 1982 by Marc Richardson and Richard Berry, founders of Goodness Grows Nursery, at an old abandoned homesite in Greene County, Georgia. The plant was in full bloom, with no sign of disease or problems. It was introduced by Goodness Grows in 1984.

‘David’ Selected at the Brandywine Conservancy, Chadds Ford, PAennsylvania by nurseryman Richard Simon and the Conservancy’s Horticulture Coordinator Mrs. F. M. Mooberry for its unusually large white flower heads and freedom from mildew. ‘David’s Lavender’ is a sport discovered in 2002 by Kathryn Litton at ItSaul Plants, Georgia.

‘Jeana’ Found in the 1990s by Jeana Prewitt of Nashville, Tennessee, growing mildew-free among "many thousands" of mildew-covered wild plants. Introduced in 2001 by the much missed Seneca Hill Perennials.

‘Speed Limit 45’ Spotted by Pierre Brunnerup, in the company of Allen Bush, by the sign on the roadside near Bush’s nursery in North Carolina and seen to be mildew free. Propagated by Bush and introduced in 2003.

These are exciting time for phlox enthusiasts, with so many new introductions. Those such as the Earlibeauty Series, with no P. paniculata in their background, seem best placed to remain mildew-resistant in the long term.

* Thank you to Charles Oliver and Allen Bush for the pictures.

A few days ago, friends here In Northamptonshire reported on some orchids they'd found. They were growing in the grass on a roadside along a very quiet country lane. They thought there were about forty early purple orchids (Orchis mascula), so I went up to take a look.

Sure enough, there they were (below) – about sixty five of them as it turned out - scattered through the long grass, their vivid colours standing out from quite a distance. They were all together, none for miles on either side. Lovely.

And it so happened that this find coincided with the a new burst of publicity for the campaign by Plantlife, the British plant conservation charity, aimed at protecting the plants growing on Britain’s roadsides. [Their website helps Brits ask your local council to protect roadside plants.]

Just a mile or two away plants of the bold tawny spikes of the uncommon parasitic plant, the knapweed broomrape (Orobanche elatior) grow on their only host, the greater knapweed (Centaurea scabiosa), along another quiet lane along with literally miles of meadow cranesbill (Geranium pratense)

Close to home over in Pennsylvania, I’ve noticed that roadsides are often the only local location for a number of interesting plants. The only clumps of false Solomon's seal (Maianthemum racemosum) (below) that I’ve seen nearby are on roadsides and I’ve also noticed more may apple (Podophyllum peltatum) and Dutchman's breeches (Dicentra cucullaria) along roadsides than anywhere else.

Partly, I presume, this is because the deer tempted to eat roadside plants are more likely to be killed by traffic and so the plants are more likely to flourish.

The key factor, of course, is mowing. Just a few hundred yards from those early purple orchids the roadside grass has been shaved like a suburban lawn. Why?! Once a year is ideal, unless the mower turns up at flowering time; mowing too early can prevent flowering and seeding and debilitate the plants. In many areas of Britain, local councils are saving money by mowing less and in some areas special marker posts are used to warn the mowers off.

And then, today, the Journal of the Hardy Orchid Society arrives and there’s an article about a stretch of roadside in Essex, east of London, which is packed with orchids. Along a busy, relatively recently constructed road, there are 350 bee orchids (Ophrys apifera) and 250 pyramidal orchids (Anacamptis pyramidalis) - a dramatic increase from 50 bee orchids and 60 pyramidal orchids six years ago. Much of this increase is down to reduced mowing brought on by budget cuts.

So, when you’re stopped in traffic, look out of the window and see what you can see. When you’re a passenger, keep your eyes peeled. But please, when you’re driving, keep your eyes on the road!

I’ve been doing some weeding. This is in our British garden where the weeds are always jumping at this time of year, especially when it’s been so wet and it’s been unwise to get on the soil.

I’ve also been having a clear out, bringing files and folders out from the back of the file cabinets and what did I find? My weed collection, three fat folders of pressed plants, that I made when I was a student at the Royal Botanic Gardens at Kew in London almost forty years ago (below right, click to enlarge).

And the first pressed plant I found in the first folder I opened was the same plant I’d just been pulling out of the garden: hairy bitter cress (Cardamine hirsuta). We have a close relative, Pennsylvania bitter cress (Cardamine pennsylvanica) in our American garden.

And this brings me to my first rule of weeding: our top weeding priority should always be to pull out are the weeds that are in flower or developing seeds. Hairy bitter cress rarely grows more then 10in/25cm high but can still can produce 700 seeds and fling them 31in/80cm, but it can also produce seeds when just two inches (5cm) high. So pull it out. Now.

Many of the traditional rules of gardening have little value but “One year’s seeding makes ten years weeding” really is true. Dandelions (below), which as annoying in Pennsylvania as they are in Northamptonshire, can produce over two hundred seeds in one seed head. So - obviously - don’t let them seed.

My second rule of weeding is always to shake the soil off the roots after you pull out the weeds and before they go on the compost heap or (in those cities with green waste recycling) in the green waste bin. You can ship out a huge amount of good soil if you’re not careful.

And my third rule of weeding is this: get them when they’re young. When nasty perennial weeds like bindweed come through at this time of year, a one inch shoot is often an indicator of yards of root underneath. Later, when their twirling stems become entwined with our garden plants, it’s all but impossible to remove them. It’s so much easier when they’re just an inch high and, at this time of year, if you disturb the plants you’re trying to protect when extracting bindweed roots they’ll soon settle down again. By the time the bindweed is strangling your cistus (top) it’s far far FAR too late.

My final rule is this: Don't spend half a day weeding and then the rest of the week nursing your aching back. I did half an hour this morning and half an hour this afternoon and I’ll try to keep that up. But if I’d spent two hours forking out weeds at a single stretch this morning (as I was tempted to do) I’d not be able to get out there again tomorrow or the next day or the rest of the week. Little and often…

OK, it's time to get back to the bindweed and dandelions and the dreaded hairy bitter cress.

Gardeners and botanists both use common names as well as scientific names when referring to plants. Using common names for plants is more widespread in North America than it is in Britain, even among botanists, and even though common names are often simply made up if there doesn’t seem to be one already in use. But common names are confusing. After all, there are more than twenty different plants, from around the world, that are called “bluebells”.

Native Americans must have had local names for many native plants when settlers first arrived in North America but the settlers didn’t bother to learn them and simply made up new ones - or, as with birds like the robin, transferred a familiar common name to a plant that looked vaguely similar to one from back home.

So when I saw a large mature sycamore (above) way across the Delaware River the other day, its white branches ghosting against the oaks and maples behind, I was reminded of this: in Europe, sycamore is used for Acer pseudoplatanus; here in North America sycamore is Platanus occidentalis. The leaves are very similar, so I presume settlers simply transferred the name. But surely, native Americans must have had a common name for P. occidentalis. After all, I’m told they used to tap it for sap in the same way as sugar maples.

In Europe, P. occidentalis is the plane tree and its hybrid with P. orientalis is a familiar city street tree. In Paris, large plane trees in the streets are pruned – literally – into a plane with all the branches parallel to the street and none overhanging.

The sycamore of Europe, Acer pseudoplatanus (below) - whose botanical name, by the way, literally translates as “the maple that looks like a plane tree”! - is a menace. There’s a huge one in our neighbor’s garden in England and its seedlings spring up all over the place. What’s worse is that they get their new roots down deep quickly so that even when they’re less than a foot high they can be tough to extract, especially between the cracks in paving.

I’d much rather have the American version.

Acer speudoplatanus image (above)  © Jean-Pol Grandmont. Licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license.

The day the echinaceas died... It was yesterday. And this is how it happened.

Echinaceas, coneflowers, and especially all the fancy hybrids that have come on the market recently, like ‘Flame Thrower’ (above) and all the doubles (below), hate bad drainage in winter. That’s what kills them. But yesterday that’s exactly what they got.

On Sunday night the temperature in our garden here in Pennsylvania went down to -10F (-23C). So, after a temperature almost as low the night before, and low temperatures for a few days before that, the ground was frozen solid to a depth it was hard to assess.

And then it snowed. Not a lot, just a couple of inches and the whole garden looked lovely. But then, yesterday, Monday, it got warmer. A whole lot warmer, and quickly. By early afternoon the temperature had risen to 48F (9C), and the snow had melted and the top inch or two of soil had thawed out as well.

But because the soil was frozen down deep, all the melted snow just sat there on the surface, in puddles – it could not drain away because the soil underneath it was frozen. Our borders were covered in pools of water, yesterday, and they’re still there this morning.

And in those puddles of thawed snow are the crowns of our last remaining echinaceas (this has happened before...) – and echinaceas hate bad drainage. So those last few may well die.

Of course, this is not a phenomenon that comes into play in Britain all that much, or in parts of the USA where the winters bring less ferocious frosts. Because if the soil is not so solidly frozen, melted snow drains away and impacts much less on our, rather sensitive, echinaceas.

But here's what's important: it reminds us that, wherever we garden, it’s bad drainage in winter that prevents us enjoying the vast range of exciting new echinaceas for years and years after we first planted them. Which is a shame, because they really are gorgeous. As you can see.

It’s always intriguing to find a plant that’s native near our American home in Pennsylvania growing near our English base in Northamptonshire (and vice versa) and the other day a stroll by the River Nene not far from our Northamptonshire house provided an enjoyable surprise. Spotted touch-me-not or jewelweed, Impatiens capensis, was growing on the bank (below, click to enlarge).

There were only a few patches, all grouped near each other, and I wondered for a moment if I myself had inadvertently introduced it on my shoes as perhaps I did in Pennsylvania when it suddenly it turned up in our garden. I walk this same stretch of river every time I’m back in England.

Mike Grant, editor of the Royal Horticultural Society magazine The Plantsman, pointed out in a comment on my piece about this plant turning up in the garden that “it has the distinction of first being recorded in the wild by the philosopher, John Stuart Mill (in Surrey in 1822)” and it is now well established in Britain, though mostly a little farther south and west from where I came across it.

In fact, we’d been thinking that perhaps we have the wrong native Impatiens in our Pennsylvania garden. Touch-me-not, Impatiens pallida, is bright yellow instead of red-speckled orange and would show up more effectively from a distance. Tomorrow I’m going to collect some seed from the plants that I’ve seen a few miles from our PA home. In which case look out for it in Northamptonshire a few years from now!

Thoughts on another non-native Impatiens species next time.

We’ve been here at the house on the lake for thirteen and a half years, and it took my five year old grandson to find an insectivorous plant that we didn’t know we had.

Monty is mad about insects – and so, by association, insectivorous plants. He has pitcher plants growing in their kitchen in the London suburbs. So when he was exploring along the banks of our lake with his dad Carl (below, click to enlarge), he knew a sundew when he saw it because he has some in a pot at home. And he knows what they do to insects. He’s not at all squeamish and watched with interest while I hit the bass his dad caught on the head so we could have it for supper.

So it turns out that we have a flourishing colony of Drosera rotundifolia (above, click to enlarge), the round leaved sundew, growing on the bank of our lake. But they’re growing in an unlikely spot. They’re only a few feet from the water, even now when the water levels are very low, but they’re on an east facing sandy bank where the soil is actually quite dry. Not the soggy sphagnum which we associate with these plants. While there is some moss, some plants are growing in bare sand.

Most of the bank is overhung by low shrubs, so only a five year old is short enough to make his way easily along there and look closely at the plants. But for two or three feet at the point where this colony is happy enough to have produced quite a few seedheads, it’s much more open.

This is a plant that grows all around the world – in a band through the Northern Hemisphere that takes in much of North America, north and eastern Europe and much of northern Russia. In Britain, it occurs mainly in Scotland, Ireland and Wales as well as southern and south west England. It's found scattered across Pennsylvania, in our county (Pike County) it’s recorded from seven sites but surely occurs more widely than that. But it took a five year old to find it on our own property.

It’s purple loosestrife season here in Pennsylvania. Swamps and other wet habitats are vivid in its purple coloring (above, click to enlarge), in some places it looks as if it’s smothered everything. This colourful European native is generally viewed as a destructive menace and many millions of dollars are spent every year in a futile attempt to eradicate it.

In Britain, by the way, where purple loosestrife (Lythrum salicaria) originated, it’s far less common and is a popular plant for bog gardens with over a dozen named varieties, two of which have been awarded the prestigious Award of Garden Merit by the Royal Horticultural Society.

In North America, purple loosestrife is generally regarded as evil but part of its reputation derives from the simple fact that it’s so colorful, it’s so obvious that it’s there. If it had dull brown flowers no one would notice. Ken Thompson, in his important book that I reviewed here recently, put it this way: “Very tall people with red hair, big tattoos and conspicuous facial scars rarely have successful careers as bank robbers, and purple loosestrife has a similar problem: it’s just too conspicuous for its own good.” He goes on to emphasize: “Recognition of loosestrife as a problem was largely based on anecdotal observations, which are likely to be particularly unreliable in the case of a tall species with such bright, obvious flowers. This is a well known problem that standard textbooks warn against: it’s easy to conclude that an otherwise rather dull wetland has been completely taken over if you look at it when loosestrife is in flower…, even if a more careful examination would reveal no such thing.”

My local experience indicates that it does not necessarily spread once the first plant arrives, and that it can also decrease over time. On the lake where we live, I spotted two plants growing together about ten years ago. I checked the whole lake last week and those two plants are still the only ones present in spite of there being many suitable habitats all along the margins. Native swamp loosestrife, Decodon verticillatus, is far far more aggressive.

And in the swamp where I first saw it flowering colorfully it has declined, as it has elsewhere, and a striking feature is that native shrubs including dogwood (Cornus) and arrowwood (Viburnum) are establishing themselves on individual clumps of purple loosestrife.

And it’s not as if purple loosestrife is entirely useless for wildlife. It’s been shown that a number of native species are more likely to grow in habitats containing purple loosestrife and in a study of over 250 plots it was found that there were more birds in those with purple loosestrife than in those without. I’ve seen around thirty individual butterflies on one plant and over sixty insect genera use it, including adult monarchs (left, click to enlarge). Birds even nest in it. Another significant study that looked carefully at this issue found that there was no difference in species richness between plots with and those without purple loosestrife.

Ken Thompson says, as he concludes his discussion of the issue: “Persecuting loosestrife is, and always has been, a waste of time.”

I was tempted to pull out those first two plants that appeared at the far end of our lake but I just left them and kept an eye on the situation. Ten years later they’re doing no harm.

Don’t get me wrong. I’m not saying that anything and everything that could be, and is, invasive should just be left alone. What I am saying is that it’s not as simple as “native good, non-native bad”. Especially when you look at how fast US native swamp loosestrife (Decodon verticillatus) can spread and the monocultures that result.


Monarch butterfly on Purple Loosestrife (Lythrim salicaria). Image © Liz West (http://www.EWestPhotos.com). Used here under Creative Commons Attribution 2.0 Generic License.