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.

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

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

Campanula portenschlagiana 'Resholdt's Variety' (Wall bellflower 'Resholdt's Variety'): Carpeting alpine with brilliant blue flowers over a long flowering period in summer.

Centaurea montana (Perennial cornflower): Large blue flowers in early summer, repeated later in year if cut back. Very attractive to bees. To 50cm. Hardy

Nepeta 'Six Hills Giant' (Catmint 'Six Hills Giant'): A vigorous sun lover which will soon make a generous clump. Spikes of tiny purple flowers over aromatic grey/green foliage.

Nepeta grandiflora 'Summer Magic' (PBR) (Catmint 'Summer Magic'): A more compact, upright growing variety of Catmint with aromatic grey foliage and spikes of lavender blue flowers. Hardy. Up to 35cm.

Nepeta x faassenii 'Kit Cat' (Catmint 'Kit Cat'): A compact variety of catmint making a neat mound of aromatic green foliage and clusters of lavender blue flowers. Hardy. Up to 30cm.