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.

Astilbe 'Amethyst': Large, upright panicles of lilac-purple flowers in summer over green ferny foliage. Excellent for damp or shady spots. Hardy. Up to 80cm.

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

Hosta 'Frances Williams': Large heart-shaped crinkled leaves with a prominent green-yellow margin. Lavender purple flowers in mid summer. Hardy. Up to 75cm.

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]

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]

Lythrum virgatum 'Dropmore Purple' (Wand loosestrife 'Dropmore Purple'): Upright spikes of purple-pink flowers in the mid-summer with lance-like foliage. Prefers a moist soil. Hardy. Up to 1m.

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

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.

Phlox paniculata 'Eventide' (Phlox 'Eventide'): Mauve-purple, scented flowers on erect stems and green lance-shaped leaves. A good vigorous selection. Hardy. Up to 90cm. AGM [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]

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]