Aconitum carmichaelii 'Arendsii' (Monkshood 'Arendsii'): Tall spires of hooded rich blue flowers in late summer. Attractive foliage spring to autumn. 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 'Burgundy Glow' (Bugle 'Burgundy Glow'): A variegated form of the superb ground cover plant with green and white leaves tinged with dark pinky red. Blue flower spikes in summer. Hardy.

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.

Ajuga reptans Black Scallop = 'Binblasca' (PBR) (Bugle 'Black Scallop'): Shiny, darkest purple-red leaves look near black. Short spikes of blue flowers in summer.

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. Hardy. Up to 1m. [Collect Only]

Aster macrophyllus 'Twilight' (Syn. Eurybia x herveyi): Lavender-blue flowers with a yellow centre in late summer. Mildew-resistant foliage. An earlier flowering variety. Height to 1m.

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

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 'Dawson's White' (Siberian bugloss 'Dawson's White'): Heart-shaped green leaves variably edged in creamy white with sprays of blue forget-me-not flowers in spring. Hardy. Up to 15cm.

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 'Sea Heart' (PBR) (Siberian bugloss 'Sea Heart'): Large heart-shaped leaves with strong silver colouration with green veins. Sprays of forget-me-not blue flowers. Hardy. Up to 30cm.

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.

Calamintha nepeta 'Blue Cloud': Spikes of small, soft blue flowers above mounds of minty scented green leaves. Loved by bees and butterflies. Hardy. Up to 30cm.

Campanula lactiflora (Milky bellflower): Clusters of blue flowers on tall stems in mid-summer. Ideal for filling out borders and adding height. Fills out quite quickly too. To 1.5m. Hardy. [Collect Only]

Campanula lactiflora 'Prichards Variety' (Milky bellflower 'Prichards Variety'): Clusters of warm blue flowers on tall stems in mid-summer. To 1.5m. Hardy. [Collect Only]

Campanula persicifolia (Peach-leaved bellflower): Tall spikes of large, cup-shaped blue flowers over slender foliage in mid-summer. To 1.2m. Hardy

Ceratostigma plumbaginoides (Plumbago, Hardy plumbago, dwarf plumbago): Brilliant blue flowers in later summer over foliage which turns redder as winter approaches. [Collect Only]

Clematis integrifolia: Non-climbing form of Clematis with small blue bell shaped flowers. Flowers on current seasons wood in late summer. Hardy. Up to 1m.

Corydalis elata: Summer flowering Corydalis with bright blue flowers above soft green foliage. Excellent in some shade in moist soil. Hardy. Up to 30cm.

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 [Collect Only]

Geranium pratense 'Cloud Nine' (Meadow cranesbill 'Cloud Nine'): An attractive double form of the familiar meadow cranesbill with lovely soft blue flowers. Strong growing. Hardy. Up to 90cm.

Geranium pratense 'Mrs Kendall Clark' (Meadow cranesbill 'Mrs Kendall Clark'): Palest purpley/grey flowers, 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 [Collect Only]

Iris sibirica (Siberian Iris): Soft, purplish blue iris flowers over strappy green foliage. [Collect Only]

Iris sibirica 'Perry's Blue' (Siberian Iris 'Perry's Blue'): Lovely pale-blue flowers with white markings over strappy green foliage. Prefers moist soil. Makes a bold clump. Hardy. Up to 85cm. [Collect Only]

Iris sibirica 'Silver Edge' (Siberian Iris 'Silver Edge'): Rich purple flowers with a fine silver picotee petal edge. [Collect Only]

Polemonium 'Northern Lights' (Jacob's Ladder 'Northern Lights'): Heavenly scented, compact form of Jacob's Ladder, with warm blue flowers

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. [Collect Only]

Pulmonaria 'Cotton Cool' (Lungwort 'Cotton Cool'): Slender leaves, so heavily spotted that they're almost completely silver. Classic pulmonaria purple/blue/pink flowers. To 30cm. Hardy.

Scabiosa caucasica 'Perfecta Blue' (Scabious 'Perfecta Blue'): Large cornflower blue frilled flowers over lance-shaped grey-green foliage. Height to 60cm. Hardy.