Acanthus hungaricus (Long-leaved bear's breeches): Architectural spires of purple/white flowers over large, dark green deeply divided leaves. Best in sun or light shade. Height to 1.2m

Acanthus mollis (Bear's Breeches): Architectural spires of purple/white flowers over large, dark green deeply divided leaves. Best in sun or light shade. Height to 1.2m.

Astrantia major 'Abbey Road' (PBR) (Hattie's pincushion, Masterwort 'Abbey Road'): Dark violet-purple flowers on dark almost-black stems above green foliage. Long-flowering. Hardy. Up to 80cm.

Campanula Iridescent Bells = 'Iribella' (PBR) (Bellflower 'Iridescent Bells'): Purple buds open to silvery-lilac bells in summer. Prefers a moisture retentive soil. Height to 80cm. Hardy

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

Centaurea montana 'Violetta (Perennial cornflower 'Violetta'): Large purple cornflower-like flowers over grey-green foliage. Very attractive to bees and butterflies. Up to 40cm. Hardy.

Cirsium rivulare 'Trevor's Blue Wonder' (Brook thistle 'Trevor's Blue Wonder'): Not blue at all, I'm afraid, but a more purplish hued form of the more familiar deepest pink Cirsium rivulare 'Atropurpureum'. Hardy. To 1.5m

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]

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 'Devon Green': Elegant hosta with tapering, dark green, fine-veined leaves. Lilac flowers in summer [Collect Only]

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.

Lavandula angustifolia 'Hidcote' (English Lavender 'Hidcote'): Classic English Lavender. Compact variety, ideal for path edging. To 40cm. Hardy [Collect Only]

Liatris spicata 'Kobold' (Gayfeather 'Kobold'): Plump spikes of purple flowers in mid to late summer. Likes dryish soil in a sunny spot. To 80cm. Hardy [Collect Only]

Ophiopogon planescapus 'Nigrescens' (Black lilyturf): Jet back strappy leaves and purplish flowers in mid-summer. Widely and rightly used in modern planting schemes against silvery plants and paving.

Penstemon 'Pensham Plum Jerkum': Plum-purple tubular flowers with white throat markings. Semi-evergreen in milder areas. Protect from hard frosts. To 70cm.

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

Perovskia 'Blue Spire' (Russian Sage 'Blue Spire'): Fine spikes of purple flowers on silver stems. Lovely winter stem effect. Hardy. Up to 1m. [Collect Only]

Perovskia 'Filigran' (Russian Sage 'Filigran'): Silvery foliage & spikes of purple flowers in mid-summer. More upright than other cultivars. Lovely winter stem effect. Hardy. Up to 1.5m. [Collect Only]

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

Thalictrum 'Elin' (Rue 'Elin'): Tallest of the Thalictrums we grow with huge heads of lavender and yellow flowers in mid-late summer. To 2m. Hardy. [Collect Only]

Thalictrum delavayi 'Hewitt's Double' (Chinese meadow rue 'Hewitt's Double'): Tiny purple pom-pom flowers dance airily above ferny grey-green foliage. Height to 1.2m. Hardy

Thalictrum delavayi 'Hinkley' (Chinese meadow rue 'Hinkley'): Dainty lilac-mauve flowers, with prominent long yellow stamens above fern-like bright green leaves. Hardy. Up to 1.5m.

Thalictrum rochebruneanum (Meadow rue): Airy sprays of lavender flowers with yellow stamens on tall purple-tinged stems. To 1.4m. Hardy [Collect Only]

Verbena bonariensis: Tall, airy but strong slender stems with flat heads of purple flowers in mid to late summer. To 1.8m. Frost-hardy.

Verbena officinalis 'Bampton' (Vervain 'Bampton'): Attractive plant with dark purple foliage and upright, wiry stems with delicate purple flowers. Long flowering. Up to 90cm. Hardy.

Veronicastrum virginicum 'Fascination' (Culver's Root 'Fascination'): One of the best cultivars with tall tapering spires of warm purple/blue flowers in mid-summer. To 1.8m. Hardy. [Collect Only]