We have found 24 plants that meet your criteria.

Monkshood ‘Aconitum Sparks Variety’ Deep violet hooded flowers on tall stems £6.99 coming soon
Hollyhock (Althea) ‘Alcea rosea Nigra’ Deep burgundy flowers £5.49 coming soon
Angelica ‘Angelica gigas’ Tall, dramatic burgundy flowers £6.99 Buy
New England Aster ‘Aster novae-angliae Violetta’ Beautiful deep purple flowers £6.99 coming soon
Price Pruned
Milky Bellflower ‘Campanula lactiflora Loddon Anna’ Soft lilac flowers on tall stems NOW £5.49 Buy
Cardoon ‘Cynara cardunculus Cardy’ A fabulous architectural plant £5.99 Buy
Price Pruned
Delphinium ‘Delphinium Black Knight Group’ Spikes of dark purple flowers with black centres NOW £5.99 coming soon
Price Pruned
Delphinium ‘Delphinium Gillian Dallas’ Stunning mauve-blue flowers with a white eye NOW £7.99 Buy
Price Pruned
Delphinium ‘Delphinium Mighty Atom’ Large, double, lavender-blue flowers NOW £7.99 Buy
Price Pruned
Delphinium ‘Delphinium Mystique’ Spires of double, purple flowers NOW £7.99 Buy
Price Pruned
Delphinium ‘Delphinium Turkish Delight’ Palest pinkish mauve flowers NOW £7.99 Buy
Price Pruned
Delphinium ‘Delphinium Walton Gemstone’ White flowers with a lavender blush NOW £7.99 Buy
Foxglove ‘Digitalis purpurea’ A native foxglove £1.25 Buy
Price Pruned
Foxglove ‘Digitalis purpurea Excelsior Group’ Perfect for a cottage-style garden NOW £5.49 Buy
Price Pruned
Foxglove ‘Digitalis x mertonensis’ Towering spikes of carmine flowers NOW £5.49 Buy
Teasel ‘Dipsacus fullonum’ Often grown by gardeners to attract Goldfinches £1.25 Buy
Price Pruned
Coneflower ‘Echinacea purpurea Magnus’ Copes well with adverse weather conditions NOW £5.99 Buy
Pride of Madeira ‘Echium candicans’ Dramatic purple spikes in early summer. Drought tolerant £5.99 coming soon
Tower of Jewels ‘Echium pininana’ Enormous spikes of blue flowers £6.99 coming soon
Joe Pye Weed ‘Eupatorium purpureum Atropurpureum’ Majestic and late-flowering £5.49 coming soon