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Garden designers choose their favourite dahlia

Three designers choose their favourite dahlias for late-season colour

Arabella Lennox-Boyd

Internationally renowned designer with more than 40 years experience chooses her favourite dahlias.

Dahlia ‘Bishop of Auckland’

© Dorling Kindersley ltd/Alamy

A most elegant, single-flowered dahlia, very prolific and adored by bees and butterflies. I plant it through Anemanthele lessoniana, Agapanthus ‘Midnight Star’ and Caryopteris x clandonensis ‘Heavenly Blue’ as if in a meadow. One of the best of the Bishop Series. Flowers: July – September. Height: 1m.

Dahlia ‘Arabian Night’

© Rachel Warne

This dahlia’s large, double, velvety dark, burgundy blooms are perfect for mixing in a border. In my own it’s surrounded by Succisa pratensis, Deschampsia and Phlox paniculata ‘Düsterlohe’. The almost black heads add a rich texture to the border. Flowers: June – September. Height: 1.2m.

Ula Maria

Garden designer, landscape architect and illustrator with a deep connection to nature chooses her favourite dahlias.

Dahlia ‘Honka Fragile’

© Tim Gainey/Alamy

This distinctive star-shaped dahlia with radiating petals that roll inwards at their tips is really striking both in a border and a cut-flower display. The white flowers are delicately edged in pink-red. Never fails to draw attention. Flowers: July – November. Height: 80cm.

Dahlia ‘Waltzing Mathilda’

© John Martin/Alamy

A semi-double dahlia with ever so slightly twisting petals that lend it a more relaxed appeal. Flowers are a wash of orangey coral pink, set off against dark purple brown stems and foliage. I love it nestled among large clumps of airy ornamental grasses. AGM. Flowers: July – November. Height: 70cm.

Jo Thompson

Award-winning garden designer, and plantswoman with a love of romantic planting chooses her favourite dahlias below.

Dahlia ‘Lilac Time’

© Peter D Anderson/ Alamy

A magnificent yet neat dinner-plate dahlia in shades of pinkish-lilac-blue. It is quite restrained and exudes self-control – I like to grow it with unruly Gaura to create a yin and yang contrast that relaxes the whole feel. Flowers: June – October. Height: 1.1m.

Dahlia ‘Purple Gem’

© Gksflorapics/Alamy

A regal dahlia, cactus in form and looking at home in many colour combinations in the border. Hints of deep lilac-blue at the centre of the flowers, becoming lighter along the petals, make this a very useful cultivar both in the border and in a vase. Flowers: July – September. Height: 1m.

Dahlia merckii

© Jason Ingram

So restrained, so elegant – single flowers of palest mother-of -pearl pink with muted yellow centres. The flowers sit high atop the tall stems and nod gently, a very lovely punctuation in the border. Unlike most dahlias, it is fairly hardy in the UK. Flowers: July – September. Height: 1.5m.