We have found 29 plants that meet your criteria.

Agapanthus africanus African Lily Globes of blue flowers in late summer £6.99 Buy
Agapanthus 'Headbourne hybrids' African Lily Showy globes of blue and white flowers £6.99 Buy
Price Pruned
Amsonia tabernaemontana Amsonia Dense clusters of ice-blue, star-like flowers NOW £5.99 Buy
Aster 'Little Carlow (cordifolius hybrid)' Aster Pretty violet-blue daisies in late summer £5.99 Buy
Nepeta subsessilis 'Cool Cat' Catmint Lavender-blue flowers. Great for a herb garden £5.99 Buy
Price Pruned
Nepeta 'Six Hills Giant' Catmint A hardy catmint with lavender flowers NOW £4.99 Buy
Nepeta subsessilis 'Washfield' Catmint Pretty catmint with bright blue flowers £5.99 Buy
Geranium 'Spinners' Cranesbill Wonderful large deep purple blue blooms £5.99 Buy
Price Pruned
Delphinium 'Cupid' Delphinium Pale sky blue flowers with a white eye NOW £7.99 Buy
Nepeta grandiflora 'Wild Cat' Giant Catmint A giant catmint with deep purple-blue flowers £5.99 Buy
Echinops bannaticus 'Blue Globe' Globe Thistle Large globes of dark blue flowers £5.99 Buy
Echinops bannaticus 'Taplow Blue' Globe Thistle Spherical, bright blue flower-heads £5.99 Buy
Echinops ritro 'Veitch's Blue' Globe Thistle Good for repeat flowering £5.99 Buy
Aquilegia vulgaris var. 'stellata Blue Barlow' Granny's Bonnet Stunning violet-blue double flowers £5.49 Buy
Price Pruned
Polemonium caeruleum Jacob's Ladder Bell-shaped, lavender-blue flowers in early summer. NOW £4.99 Buy
Aster x frikartii 'Mönch' Michaelmas Daisy Lavender-blue, daisy flowers £5.99 Buy
Price Pruned
Campanula lactiflora 'Pritchard's Variety' Milky Bellflower Masses of bell-like lilac flowers NOW £4.99 Buy
Price Pruned
Phlox paniculata 'Blue Paradise' Perennial Phlox Fragrant violet flowers all summer NOW £5.49 Buy
Perovskia 'Blue Spire' Russian Sage Violet-blue flowers and silvery foliage. Great planted en masse £7.99 Buy
Salvia patens Sage Large, stunning blue blooms £5.99 Buy