Last time I discussed a familiar roadside plant here in Pennsylvania, brought with the settlers to make soap – Saponaria officinalis, soapwort. But alongside it we often find a very different, but equally robust perennial, from Asia this time, the double-flowered daylily Hemerocallis fulva ‘Flore Pleno’.

If it wasn’t for the vast variety of more recent daylily hybrids, this would be on everyone’s list of top perennials. With its long season of 6in/15cm double flowers, each a nest of ochre orange petals, the outer petals are broad and bold with a bright red flash, the inner ones narrower with a less dramatic mark.

This is a triploid plant, with an in between number of chromosomes, so it cannot set seed and this helps prolong its flowering season which is most of July, often starting in late June or extending into August depending on the local climate. It reaches about 3ft/90cm, is dependably self-supporting and unlike many daylilies spreads by stolons to make large patches.

‘Flore Pleno’ is also reckoned to be the top choice for cooking, deep frying in particular. I’m told that with so many more petals in its large flowers it makes much a more of a mouthful than the usual six petalled daylily. The tubers are also edible.

Hemerocallis fulva grows wild in many Chinese provinces as well as in India, Japan, Korea and Russia. ‘Flore Pleno’ was brought to Europe from Mauritius by the Reverend W. Ellis and passed to the influential British nursery Veitch & Sons some time before 1861. From there it came to North America where it flowered dependably with little or no care – as it does along roadsides

‘Flore Pleno’ is sometimes confused with another daylily, H. fulva ‘Kwanso’. Both are double, and both have orange flower with red marks on the petals. However, the most clear distinguishing feature is that ‘Flore Pleno’ has 15 to 18, strongly recurved petals usually arranged rather neatly, while ‘Kwanso’ has seven to twelve petals, often in a rather muddled-looking arrangement. Neither ever produced seed, although both have partially fertile pollen.

Daylily enthusiasts often look down on this plant because it’s less refined than modern hybrids, in a less surprising color and without the intricate patterning of so many recent introductions. But, if you like the color, and are looking for a summer perennial that you can plant and pretty much ignore then this is it.

At least when you see this plant by the side of the road, the answer to the question: “What’s that doing there?” is clear. This is soapwort, Saponaria officinalis, growing by the roadside here in Pennsylvania and since earliest times it’s been used to make soap.

Found wild in Southern Europe, and growing over much of Britain but perhaps native only in the south west (the botanists seem undecided), this pale form is the one seen in here in PA though in some areas a darker rose pink form is seen, and a pale semi-double form (‘Rosea Plena’) also sometimes establishes itself in the wild.
It was brought to North America by colonists specifically for its use as soap and for use in brewing, and long ago escaped from homesteads. It can be made into a very gentle soap - it’s said to have been used to clean the Bayeux Tapestry - and there’s little in the North American native flora that will do the job, especially in colder areas. Soapwort is hardy down to zone 3 (-40C/-40F). Boil it in rainwater to create a mild soapy lather. It’s been used to help create a head on beer, and is also used to make halva.

To be honest, the plant is a bit of a thug, even in poor soil it grows vigorously as long as it has plenty of sun, and it takes the salty run-off from roads in its stride. In fact it’s so adaptable that it’s naturalized in every American state except Alaska and Hawaii. Here in Pennsylvania, it often grows along roadsides with double-flowered daylilies – about which more next time.

I still get skeptical looks when I point out that this Tuscan kale is a great ornamental plant. I think many people are still worried even about eating kale – which they still think of some sort of punishment – let alone growing it as an ornamental.

So here’s the kale variously known as ‘Nero di Toscano’, Tuscan kale, ‘Lacinato’ and cavolo nero (and also known, according to Wikipedia, as Tuscan cabbage, Italian kale, Dinosaur kale, black kale, flat back cabbage, palm tree kale, and black Tuscan palm)… here it is growing in our Pennsylvania garden. Looks great, doesn’t it?

Behind it is one of the more recent variegated weigela introductions French Lace (‘Brigela’) also known as Moulin Rouge whose splendid variegations ensure that the structure and colour of the kale really stands out. A little ‘Bright Yellow’ chard and variegated Masquerade ('Notbud') buddleia peep into the picture.

‘Nero di Toscano’ kale, or whatever you like to call it, has been grown for centuries. This not only makes clear its resilience and its lasting value, but over the years it has also become rather variable; sometimes, when you grow it, no two plants are quite the same.

Now, a new selection from Britain called ‘Black Magic’ (below, click to enlarge) is becoming available which is much more dependably uniform, and also comes with shorter stems so it's less likely to fall over. As I said when I wrote it up for my Royal Horticultural Society New Plans blog: “As well being uniform in colour, the foliage of ‘Black Magic’ is darker than earlier forms and with more intense puckering. The leaves are a little narrower, it’s much less likely to bolt, and its frost resistance is even better than before.” So why not try it?

And if you’re still skeptical about eating it, try homemade baked kale chips – The Huff Post will tell you how to make them.

In North America, kale ‘Black Magic’ is available from Veseys.

In Britain, kale ‘Black Magic’ is available from Suttons.

Powerhouse Plants, Plants For All Seasons, are individual varieties which provide color and interest for at least two seasons of the year and not just a fleeting flush of flowers. I feature over five hundred of them in my latest book, Powerhouse Plants, and every month in Gardener’s World, Britain’s top-selling garden magazine (and also available in the US, from Barnes & Noble stores for example) I focus on one very special Plant For All Seasons, highlighting three features which bring color to the garden at different times of the year. This month, in the magazine, I feature Hydrangea aspera subsp. sargentiana.

And every month here on my Transatlantic Gardener blog I bring you details of another. Last month it was a recently introduced shrub, Kolkwitzia amabilis Dreamcatcher (‘Maradco’). This month it’s the old favorite Rosa rugosa.

One of the toughest shrubs you’ll come across, Rosa rugosa (above, click to enlarge) features a long season of large single flowers overlapping in season with large, long-lasting red hips. The deeply veined foliage is attractive too, most forms have a lovely fragrance, and they rarely grow taller than 8ft/2.4m, usually less.

And yes, this is a tough plant. It grows naturally in areas of China and Siberia where the sea freezes over so it takes ferocious winters as well as salt spray. It flowers well in a wide variety of soils, including almost pure sea sand, and needs little pruning except perhaps to shorten an occasional long shoot. And that’s just as well because the stems are exceptionally thorny – so it’s ideal as an informal hedge to keep out the neighbor’s dog.

As well as the wild type with its purplish pink flowers and large, flattened red hips there are some fine selections and hybrids, all with excellent hips:
‘Alba’ – single white flowers
‘Blanc Double de Coubert’ – double white flowers with an especially good scent
‘Fru Dagmar Hastrup’ – silvery pink flowers
‘Robusta’ – bright red flowers

But avoid ‘Roserie de l’Hay’ which rarely produces any hips at all.

Please take a look at Plants For All Seasons in Gardeners World magazine each month. And check back here for monthly posts about other Powerhouse Plants – the Plants For All Seasons.

You can order my book, Powerhouse Plants in Britain from amazon.co.uk

You can order my book, Powerhouse Plants in North America and the rest of the world from amazon.com

Or you can find out more about the book at the Powerhouse Plants webpage.

Subscribe to Gardeners' World magazine In North America,Gardeners' World magazine is also available in Barnes & Noble and other good bookstores.