You may remember from your childhood, AA Milne’s chipmunk ‘lived in a bed of delphiniums (blue) and geraniums (red)’. This poem, The Dormouse and the Doctorfrom When we were very young always haunts my mind, conjuring up images of English gardening in the 1920s.
Since then, delphiniums have become the star of tall summer herbaceous borders. They are popular home garden plants, their tall spires looking beautiful against the branches of Crambe cordifoliavibrant YarrowSagittarius astrantia and agapanthus.
The ancient Greeks coined the name ‘delphinium’, reminiscent of dolphins because of their newly grown buds. They are members of the Family Ranunculaceae and there are many different varieties, including the Elatum hybrid, which have been bred over the years to be suitable for gardening.
It is thought that the Delphinium species of the Belladonna group originated from hybrids between garden delphiniums and other species. DelphiniumsNative to Russia and China. Pacific hybrids, developed in California in the mid-20th century, tend to be shorter and better adapted to drought conditions.
The first Elatum hybrids were produced by Victor Lemoine in the mid-19th century in France, before being brought to England by James Kelway in 1859, and extensively bred by Charles Langdon and James Blackmore in the early 20th century. Established in 1901, Blackmore and Langdon remains the specialist in Elatum hybrids, with Simon, Stephen and Nicholas Langdon, Charles’ great-grandson, now co-directors. The only business still run by the family, it has exhibited every year since its inception. Chelsea Flower Show In 1913 they supplied delphiniums to Winston Churchill at Chartwell, and to the royal family at Highgrove, Clarence House and Buckingham Palace. Simon Langdon believes that they also sold delphiniums to Claude Monet, and it was their delphiniums that appeared in a photograph of the artist at Giverny in 1908.
I find it hard to disagree with Simon’s – and the Shrew’s – view that delphiniums should really be blue. Simon believes that white delphiniums are best used to highlight pure blue, rather than as a stand-alone plant. Certainly, attractive combinations include white delphiniums Delphinium ‘Alisa’, yellow eyes D. grow up ‘Olive Poppleton’, or ‘Lilian Bassett’ has slender stems, black eyes next to pure blue D. grow up ‘Langdon’s Blue Lake’ and ‘Loch Leven’ or ‘Faust’ purple blue.
There have been attempts to grow red delphiniums but according to Simon they tend to act as annuals and will flower but not overwinter. However, one long-term result of these schemes is the apricot pink ‘Princess Caroline’. Pink is increasingly popular and the range of shades now includes the bright pink ‘Jenny Agutter’ and the paler, RHS Award of Garden Merit winner, ‘Foxhill Nina’.
And there is a remarkable range of colours within the blues alone – from the palest blue, through pure blue to mauve and deep purple-blue. For the front to mid-border, you might want to alternate pale blue ‘Ballkleid’, blue ‘Piccolo’, purple-blue ‘Atlantis’ or deep blue ‘Volkerfrieden’, all from the Belladonna group, with white, lupine or red phlox. Astrantia major. Behind, towering ‘Loch Leven’, ‘Langdon’s Blue Lagoon’, dark lilac ‘Michael Eyres’, or lilac ‘Susan Edmunds’, with tall, pale yellow Cephalaria gigantea has flowers up to 15cm wide.
Other companions for delphiniums include shrub roses and orchids such as Rosa ‘Veilchenblau’. For a less formal look, consider grasses: Stipa gigantea and Calamagrostis x acutiflora ‘Karl Foerster’ will add interest when the delphiniums fade.
Delphiniums need space, especially Elatum hybrids, which like air around their roots and room when newly planted. Elatums have 10-15 closely packed flower clusters, large palmate leaves and will grow to around 1m when mature. Many can reach 2m. Belladonna delphiniums tend to be smaller, with larger spaces between single caped flowers, and are more low maintenance – like wild larkspur.
For all their majesty, delphiniums are surprisingly easy to grow, given the right conditions. Ideally, they need six hours of full sun a day, or they may not flower. They prefer chalk to clay, as they hate to sit in water, and grow best in cold winters when the ground is frozen solid. After recent mild, wet winters, they have been less prolific.
To encourage a second flush, be bold and cut off the stem as soon as they look tired, then feed and water them well. With proper care, delphiniums will live for many years: the Royal Parks operate on the basis that they lose their vigour after about eight years. But Simon Langdon recently received a complaint from a customer about his ‘Strawberry Fair’ delphinium, which he felt had died prematurely. It turned out to have been bought in 1977.
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Ensure that the delphinium is in a sunny location and grows in sandy, loose or well-drained soil fertilized with well-rotted horse or cow manure. Plant in a spacious hole, with the crown of the plant at ground level.
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If planting delphiniums in groups, space them at least 45cm apart and 30cm away from other herbaceous plants. “They don’t mind fighting for their space once they’re established, but they need space to grow,” advises Simon Langdon.
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Stake each tree individually as soon as leaves appear in April to avoid the plant falling over when in heavy bloom.
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dolphins grow up Can be propagated by sowing seeds in fall or spring.
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Propagate Elatum and Belladonna hybrids by take root cuttings Use 3-6 inch (7.5-15cm) cuttings in early spring. Root in gritty compost in a greenhouse or conservatory. Do not allow the cuttings to dry out. Repot the cutting as it grows and plant out after the last frost in late May.
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Best time to divide delphinium is between March and April.
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Cheesy are the main predators of delphiniums and constant vigilance is the watchword, throughout the autumn and winter when they lay their eggs, and in the spring and summer. Trevor Jones, head gardener at Alnwick, uses Strulch as an effective slug deterrent. It also keeps weeds at bay.
