Aconitum napellus (Monkshood): Dark blue hooded flowers over finely divided foliage. This Aconitum flowers early, in late spring/early summer. Height to 1.5m. Hardy. [Collect Only]

Ajuga reptans (Bugle): Superb ground cover plant with purplish green leaves and blue flower spikes in summer. Very attractive to bees

Ajuga reptans 'Catlin's Giant' (Bugle 'Caitlin's Giant'): Superb ground cover plant with bronze-purple leaves and blue flower spikes in summer. Semi-evergreen. Very attractive to bees.

Ajuga reptans 'Variegata' (Bugle 'Variegata'): Superb ground cover plant with green and white variegated leaves and blue flower spikes in summer. Very attractive to bees.

Amsonia tabernaemontana (Blue dogbane): Starry blue flowers on strong stems with willowy green leaves. Hardy. Up to 90cm. [Collect Only]

Aster 'Little Carlow' (Syn. Symphyotrichum 'Little Carlow' (cordifolium hybrid)): Large sprays of small purplish blue flowers in autumn. Very reliable, easy to grow perennial. Up to 1m.

Brunnera macrophylla (Siberian bugloss): Heart shaped green leaves, with sprays of palest blue flowers in spring. Good in shade. Up to 30cm. [Collect Only]

Brunnera macrophylla 'Alchemy Silver' (Siberian bugloss): Large silver heart shaped leaves with dark green veining. Bright blue forget-me-not like flowers in spring. Great for shady areas. Hardy. Up to 40cm.

Brunnera macrophylla 'Alexander's Great' (PBR) (Siberian bugloss 'Alexander's Great'): Statement foliage plant for shade. Large, heart-shaped, silver leaves. Light-blue forget-me-not-like flowers in Spring. Hardy. Up to 40cm.

Brunnera macrophylla 'Hadspen Cream' (Siberian bugloss 'Hadspen Cream'): Large, heartshaped green leaves with wide cream margin. Sprays of forget-me-not blue flowers in spring. Hardy. Up to 45cm.

Brunnera macrophylla 'Jack Frost' (PBR) (Siberian bugloss 'Jack Frost'): Large, heartshaped silver leaves with green veins and leaf edges. Sprays of forget-me-not blue flowers in spring. Shade-loving plant. Hardy. Up to 45cm.

Brunnera macrophylla 'Variegata' (Siberian bugloss 'Variegata'): Large, heartshaped leaves with bold variegation. Sprays of forget-me-not blue flowers in spring. Superb shade plant. Hardy. Up to 45cm.

Campanula lactiflora 'Prichards Variety' (Milky bellflower 'Prichards Variety'): Clusters of warm blue flowers on tall stems in mid-summer. To 1m. Hardy.

Ceratostigma plumbaginoides (Plumbago, Hardy plumbago, dwarf plumbago): Brilliant blue flowers in later summer over foliage which turns redder as winter approaches. Stunning ground cover plant for sheltered spots. Not fully hardy in colder parts of UK. To 20cm. Frost-hardy

Geranium 'Alan Mayes' (Cranesbill 'Alan Mayes'): Long flowering geranium with bright blue flowers with purple veining. Clumps of hairy green leaves, turning red in autumn. Hardy. Up to 45cm.

Geranium 'Blue Cloud' (Cranesbill 'Blue Cloud'): Tall cultivar with pale blue flowers & dark purple veining above deeply divided green leaves. Long-flowering. Hardy. Up to 90cm.

Geranium 'Brookside' (Cranesbill 'Brookside'): A reliable, robust variety with large rich blue flowers over a mound of deeply divided leaves. Height to 45cm. Hardy

Geranium 'Nimbus' (Cranesbill 'Nimbus'): Makes medium sized domes of finely divided foliage smothered in purplish blue flowers in early summer. To 50cm. Hardy

Geranium 'Orion' (Cranesbill 'Orion'): A dome of deeply divided foliage, smothered in large blue flowers from early summer onwards

Geranium himalayense 'Baby Blue' (Cranesbill 'Baby Blue'): Large blue cup shaped flowers with purple veining. Spreading habit, forming a carpet of deeply divided leaves. Hardy. Up to 30cm.

Geranium himalayense 'Gravetye' (Cranesbill 'Gravetye'): Purplish blue cup shaped flowers with purple veining. Pink tinged early foliage, spreading habit

Geranium pratense 'Mrs Kendall Clark' (Meadow cranesbill 'Mrs Kendall Clark'): Palest purpley/grey flowers with beautiful veining, makes a good mound of foliage. Hardy. To 40cm.

Geranium Rozanne = 'Gerwat' (PBR) (Geranium 'Rozanne'): Noted for its large blue, white centred flowers and very long flowering period. A fine border geranium. Doesn't run. To 30cm. Hardy

Hepatica nobilis: Pretty bowl shaped blue flowers in early spring.

Phlox paniculata 'Blue Paradise' (Phlox 'Blue Paradise'): An attractive form with bright blue-purple heavily scented flowers. Good for cutting. Hardy. Up to 1.2m.

Polemonium Bressingham Purple = 'Polbress' (Jacob's Ladder 'Bressingham Purple'): Striking purple foliage topped with purplish blue flowers in early summer. Hardy. To 60cm [Collect Only]

Polemonium reptans 'Stairway to Heaven' (PBR) (Jacob's Ladder 'Stairway to Heaven'): Superb variety with attractive variegated foliage and lavender blue flowers. To 50cm. Hardy

Pulmonaria 'Blue Ensign' (Lungwort 'Blue Ensign'): Rich blue flowers in spring over unspotted dark green foliage. A reliable hardy perennial. Up to 30cm.

Pulmonaria 'Trevi Fountain' (Lungwort 'Trevi Fountain'): Long flowering, with blue flowers over silver-speckled leaves in spring. Great in shade. Hardy. Height to 30cm.

Salvia uliginosa (Bog Sage): Branched stems of clear blue flowers and lance-shaped leaves. Needs a sunny spot but with moist soil. Late flowering. To 2m.