We have found 39 plants that meet your criteria.

African Lily ‘Agapanthus africanus’ Globes of blue flowers in late summer £5.99 Buy
Aster ‘Aster Little Carlow (cordifolius hybrid)’ Pretty violet-blue daisies in late summer £5.99 Buy
Michaelmas Daisy ‘Aster x frikartii Monch’ Lavender-blue, daisy flowers £5.99 Buy
Price Pruned
Milky Bellflower ‘Campanula lactiflora Pritchard's Variety’ Masses of bell-like lilac flowers NOW £4.99 Buy
Price Pruned
Delphinium ‘Delphinium Cupid’ Pale sky blue flowers with a white eye NOW £7.99 Buy
Globe Thistle ‘Echinops bannaticus Blue Globe’ Large globes of dark blue flowers £5.99 Buy
Sea Holly ‘Eryngium x zabelii Jos Eijking’ Spiny metallic-blue flowers in late summer £7.99 Buy
Bearded Iris ‘Iris Fort Apache’ Luscious maroon blooms £6.99 Buy
Price Pruned
Great Purple Flag ‘Iris pallida Argenteovariegata’ Stunning grey-green and white variegated leaves NOW £5.99 Buy
Siberian Iris ‘Iris sibirica Caesar's Brother’ Intense violet flowers. Great in boggy ground £5.99 Buy
Siberian Flag ‘Iris sibirica Perry's Blue’ Looks great planted in bold clumps £5.99 Buy
Siberian Flag ‘Iris sibirica Tropic Night’ Violet flowers with yellow throats. Good for boggy ground £5.99 Buy
Catmint ‘Nepeta subsessilis Cool Cat’ Lavender-blue flowers. Great for a herb garden £5.99 Buy
Catmint ‘Nepeta subsessilis Washfield’ Pretty catmint with bright blue flowers £5.99 Buy
Russian Sage ‘Perovskia Blue Spire’ Violet-blue flowers and silvery foliage. Great planted en masse £7.99 Buy
Price Pruned
Perennial Phlox ‘Phlox paniculata Blue Paradise’ Fragrant violet flowers all summer NOW £5.49 Buy
Sage ‘Salvia patens’ Large, stunning blue blooms £5.99 Buy
Salvia May Night ‘Salvia x sylvestris Mainacht’ Large indigo-blue flowers £5.99 Buy
African Lily ‘Agapanthus Headbourne Hybrids’ Showy globes of blue and white flowers £5.99 Buy
Price Pruned
Amsonia ‘Amsonia tabernaemontana’ Dense clusters of ice-blue, star-like flowers NOW £5.99 Buy