We have found 15 plants that meet your criteria.

Teasel ‘Dipsacus fullonum’ Often grown by gardeners to attract Goldfinches £1.25 Buy
Foxglove ‘Digitalis purpurea’ A native foxglove £1.25 Buy
Verbena ‘Verbena bonariensis’ Lilac-purple flowers £5.49 Buy
Price Pruned
Milky Bellflower ‘Campanula lactiflora Loddon Anna’ Soft lilac flowers on tall stems NOW £5.49 Buy
Price Pruned
Foxglove ‘Digitalis purpurea Excelsior Group’ Perfect for a cottage-style garden NOW £5.49 Buy
Culver's Root ‘Veronicastrum virginicum Lavendelturm’ Long tapering flower spires £5.49 Buy
Price Pruned
Foxglove ‘Digitalis x mertonensis’ Towering spikes of carmine flowers NOW £5.49 Buy
Cardoon ‘Cynara cardunculus Cardy’ A fabulous architectural plant £5.99 Buy
Price Pruned
Coneflower ‘Echinacea purpurea Magnus’ Copes well with adverse weather conditions NOW £5.99 Buy
Angelica ‘Angelica gigas’ Tall, dramatic burgundy flowers £6.99 Buy
Delphinium ‘Delphinium Gillian Dallas’ Stunning mauve-blue flowers with a white eye £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
Delphinium ‘Delphinium Turkish Delight’ Palest pinkish mauve flowers £7.99 Buy
Price Pruned
Delphinium ‘Delphinium Walton Gemstone’ White flowers with a lavender blush NOW £7.99 Buy