Echinacea: how to grow & choose the best

New breeding has brought us echinacea in a wide range of cheery colours as well as different flower forms. Val Bourne explores the options, and how to get the best from them.

Echinaceas are real dazzlers in the late-summer border: sturdy daisies standing erect with flowers that resemble sets of spinning saucers. The colourful sun-ray petals surround bronzed, almost metallic cones. These prickly centres also give echinacea its name, for Ekhînos is Greek for hedgehog.

They’re insect-friendly, too, each central disc containing between 200 and 300 florets with a nectar pot at its base, which makes the flowers ideal for butterflies and bees. It doesn’t end there though: the buds resemble intricate coronets and, after the flowers have faded, the dark central cone persists into winter and forms a dramatic silhouette. This ability to fade gracefully into winter has made echinaceas essential for those wishing to emulate Piet Oudolf’s prairie planting style and it’s the seed-raised echinaceas that do this best.

There are nine echinacea species and four subspecies distributed across the eastern and mid-western states of America. They’re found naturally on prairies, and the area of greatest species richness is in the grasslands of Oklahoma and Missouri. Both get hot, humid summers and long, cool winters but hardiness isn’t generally a problem, because they are often protected by snow cover. The wet, stop-start winters in the UK, however, don’t suit them as well.

The most commonly grown garden type, known as the purple coneflower or Echinacea purpurea, has fibrous roots and will flag in dry conditions. In the wild it’s often found on wetter soils adjacent to rivers and streams. Echinacea purpurea arrived here in 1699 when the English clergyman-naturalist John Banister (1654–1692) sent seeds to Jacob Bobart the Younger, Keeper of the Oxford Botanic Garden, from Virginia. The roots were already being used as a medicinal cure-all by several indigenous American tribes, to treat a range of ailments. Many take echinacea tablets today, to boost their immune systems.

The first echinacea to grab the gardener’s attention through its sheer flower power was the seed-raised, large-flowered E. purpurea ‘Magnus’. It won the Perennial Plant of the Year in America in 1998. Plants and seeds of ‘Magnus’ are still available – echinaceas can be raised from seed and subsequent plants will persist for roughly five years. Other good seed strains include E. ‘Rubinstern’ (literally ‘Ruby Star’), an improved form of ‘Magnus’ that is widely grown at Great Dixter. E. ‘White Swan’ is another reliable seed strain that is also widely available.

The first double was discovered as a seedling in a field of E. ‘Magnus’ in 1997 by Jan van Winsen of Warmond in The Netherlands, and marketed as ‘Razzmatazz’. It’s a good plant that’s survived in my garden. Now there is a wide range of doubles, many of them raised in Holland by Arie Blom. These ‘fancy echinaceas’, which are complex hybrids between species, are nearly always sterile. They flower for longer because they’re unable to set seed, but this means they have to be raised by the micropropagation technique of tissue culture. The resulting plants can have lavish tops but, in my opinion, poor root systems. As a result, these echinaceas often fail to overwinter in British gardens.

The colour range extends beyond pink and white. Dr Jim Ault of the Chicago Botanic Garden experimented with hybridising pink and white forms of Echinacea purpurea, with the pink-flowered E. angustifolia and E. tennesseensis along with the clear-yellow E. paradoxa. Ault’s work gave rise to the sunset-orange ‘Art’s Pride’ in 2004. A paler sport was named ‘Mango Meadowbrite’. These did not endure British winters, since the breeding was based on E. tennesseensis – a less than vigorous species.

More sunset shades were raised by Richard Saul of Saul Nurseries in Atlanta, Georgia, and named the Big Sky Series. These were based on the more resilient E. purpurea and include ‘Sunrise’, ‘Sunset’, ‘Twilight’, ‘Harvest Moon’ and ‘Sundown’. We now have peaches, green-whites and clear yellows as well as vivid pinks and reds. American breeders, faced with searing summers, produce brighter colours and shorter plants better suited to containers. Terra Nova have added ‘Tomato Soup’ among others. All US echinaceas are raised under Californian skies.

Although gardeners have a far greater choice than they used to, if you want an enduring stand of echinaceas it’s far easier to achieve with the single pink or white single daisies raised from seed. The ritzier doubles and the colourful varieties raised by tissue culture, are definitely more of a challenge to grow in British gardens. My instinct is that the Dutch-raised tissue-cultured varieties will be better survivors than the American-bred ones, purely because they’ve endured a European climate.

Chris Reed of Ball Colegrave, a major supplier of American echinaceas to garden centres, believes the sensible thing is to see them as pots of colour for late-summer into autumn. Containerising them makes sense, because it’s then possible to protect them from winter wet – as you would an agapanthus.