We have found 17 plants that meet your criteria.

Price Pruned
Allium ‘Allium cristophii’ Huge globes of star-like, lilac flowers NOW £5.99 Buy
Allium ‘Allium hollandicum Purple Sensation’ Rich, deep purple globes £5.99 Buy
Price Pruned
Granny's Bonnet ‘Aquilegia vulgaris var. stellata Black Barlow’ Striking dark purple, double flowers NOW £4.99 Buy
Geranium ‘Geranium sylvaticum Birch Lilac’ Great for a woodland setting £5.99 Buy
Price Pruned
Bergamot ‘Monarda Ou Charm’ Pretty, pink flowers and purple bracts NOW £5.49 Buy
Phlox ‘Phlox paniculata Franz Schubert’ Wonderful, fragrant, lilac flowers £5.99 Buy
Price Pruned
Columbine ‘Aquilegia McKana Hybrids’ Bonnet-like flowers in a range of colours NOW £4.99 Buy
Granny's Bonnet ‘Aquilegia vulgaris William Guinness’ Unusual purple-black flowers £5.49 Buy
Michaelmas Daisy ‘Aster novi-belgii Purple Dome’ Masses of violet-purple flowers in late summer £5.99 Buy
Masterwort ‘Astrantia major Rubra’ Gorgeous plum-coloured flowers £5.99 Buy
Price Pruned
Dusky Cranesbill ‘Geranium phaeum Lily Lovell’ Iridescent saucers of purple flowers. Good for shade NOW £5.49 Buy
Armenian Cranesbill ‘Geranium psilostemon’ Gorgeous magenta flowers with black centres £5.99 Buy
Giant Catmint ‘Nepeta grandiflora Wild Cat’ A giant catmint with deep purple-blue flowers £5.99 Buy
Phlomis ‘Phlomis cashmeriana’ Distinctive whorls of lilac flowers in high summer £5.99 Buy
Perennial Phlox ‘Phlox paniculata Amethyst’ Tall variety with violet flowers £5.99 Buy
Price Pruned
Jacob's Ladder ‘Polemonium caeruleum’ Bell-shaped, lavender-blue flowers in early summer. NOW £4.99 Buy
Price Pruned
Sweet Violet ‘Viola odorata’ Sweetly fragrant flowers NOW £4.99 Buy