Aster radula 'August Sky' (Syn. Eurybia radula 'August Sky'): Neat mounds of purple flowers on a compact plant from June to August

Centaurea 'Jordy' (Perennial cornflower 'Jordy'): Beautiful maroon-purple flowers over felty silvery-green foliage. [Collect Only]

Erigeron 'Adria' (Fleabane 'Adria'): Mound forming perennial forming masses of semi-double purple flowers with central yellow disc. Hardy. Up to 60cm.

Erigeron 'Dunkelste Aller' (Fleabane 'Darkest of all'): Large purple daisy flowers over a long season in summer. Great in sunny, dry borders. To 30cm. Hardy [Collect Only]

Festuca amethystina: Evergreen grass with elegant, dusky purple arching flower stalks very early in season, for a grass.

Geranium clarkei 'Kashmir Purple' (Cranesbill 'Kashmir Purple'): Rich purple flowers with darker veins above attractive finely divided dark green leaves. Good as ground cover. Hardy. Up to 50cm.

Geranium maculatum 'Beth Chatto' (Spotted cranesbill 'Beth Chatto'): Very pretty palest purple flowers held above attractive green foliage. To 50cm. Hardy.

Geranium maculatum 'Vickie Lynn' (Spotted cranesbill 'Vickie Lynn'): Pale lavender flowers above a clump of fresh green divided leaves. Prefers soil that doesn't dry out in summer. Hardy. Up to 45cm.

Geranium wlassovianum: Warm purple flowers over attractive velvety foliage. Excellent autumn foliage colour.

Hosta 'Big Daddy': Lovely large blue-green leaved Hosta, with some puckering to the leaves. Large clump-forming. Lilac flowers in summer. Hardy. Up to 60cm. [Collect Only]

Hosta 'Fireworks' (PBR): Gleaming ivory leaves with multi-hued green leaf edge markings. Very upright habit. To 50cm. Hardy.

Hosta 'Patriot': Large green leaves cleanly edged in white. Lilac flowers in summer. To 50cm. Hardy.

Hosta 'Praying Hands': Very upright, rippled leaves. Leaves are green, narrowly edged in white and curl up. Lilac flowers in summer. Hardy. Up to 40cm. AGM.

Hosta 'Sum and Substance': Large, bright green leaves. lavender flowers, good in shade or sun. Hardy. To 60cm high and wide. [Collect Only]

Kalimeris yomena 'Shogun' (Japanese Aster): Lavender, daisy flowers above attractive variegated leaves. Flowering late summer. Prefers full sun/moist soil. Hardy. Up to 60cm. [Collect Only]

Liriope muscari 'Big Blue' (Blue turf lily 'Big Blue'): Spikes of vibrant purple flowers in autumn, larger than the usual form, evergreen strappy foliage. Good for dry shade. Hardy. Up to 50cm

Liriope muscari 'Royal Purple' (Blue turf lily 'Royal Purple'): Spikes of deep purple flowers in autumn above dark-green evergreen strappy foliage. Can tolerate dry shade. Hardy. Up to 50cm.

Lobelia x speciosa 'Hadspen Purple' (PBR): Dramatic spikes of purple flowers in late summer, above lance-shaped purple flushed leaves. Needs damp soil in summer. Hardy. Up to 60cm.

Penstemon 'Pensham Czar': Bright purple flowers with white throat. Very long flowering - up to five months, especially if regularly dead-headed. To 50cm. Frost hardy.

Penstemon 'Raven': Darkest purple-red tubular flowers over semi-evergreen foliage.

Salvia nemorosa 'Caradonna' (Balkan Clary 'Caradonna'): Rich purple spikes in early summer - just in time for Chelsea Flower Show at which is widely used.To 50cm. Hardy

Salvia nemorosa 'Ostfriesland' (Balkan Clary 'Ostfriesland'): Masses of upright spikes of purple flowers in mid summer. Easy and trouble free. To 50cm. Hardy

Stachys officinalis 'Hummelo' (Betony 'Hummelo'): Upright spikes of rosy purple flowers above pointed dark green foliage. Very attractive to bees. To 50cm. Hardy.