Angelica gigas: Magnificent plant with huge domes of purple flowers in summer, and attractive seed heads. Biennial/short-lived perennial. Up to 2m.

Anthriscus sylvestris 'Ravenswing' (Purple cow parsley): A dark leaved form of the common cow parsley. To 1.5m. Hardy. Tends to be biennial.

Aster laevis 'Arcturus' (Syn. Symphyotrichum laeve 'Arcturus'): Clouds of lilac/purple flowers over almost black stems. Hardy and reliable late summer/autumn flowerer. Hardy. Up to 1.3m.

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

Delphinium 'King Arthur': A pacific hybrid perennial with tall spikes of plum purple flowers with white eyes. To 1.5m Full sun. Hardy.

Echinacea purpurea (Coneflower): Large rosy-purple daisy-like flowers with a large brown central cone. Very attractive to bees and butterflies. Long flowering season [Collect Only]

Molinia caerulea 'Heidebraut' (Purple moor grass 'Heidebraut'): Elegant flower stalks with slender purple flower heads in late summer. Makes an upright, vase shape. To 1.2m. Hardy

Molinia caerulea 'Poul Petersen' (Purple moor grass 'Poul Petersen'): Very handsome grass, much beloved by modern garden designers. Makes an upright, vase shape of burnished gold in autumn.

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 'Splendide' (Rue 'Splendide'): Superb Thalictrum with clouds of purple flowers open for a very long time in late summer. Hardy. Up to 1.5m

Thalictrum delavayi (Chinese meadow rue): Dainty lilac-mauve flowers 2cm in width, with prominent creamy yellow stamens above fern-like bright green leaves. Hardy. Up to 1.5m.

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 delavayi var. acuminatum (Chinese meadow rue): Sprays of lilac flowers, soft ferny foliage. May need a little support. Lovely in dappled shade. To 1.5m.

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

Vernonia arkansana 'Mammuth' (Ironweed 'Mammuth'): Very tall with purple flowers. Good for growing amongst tall grasses and other classic prairie plants. Loved by bees. Hardy. Up to 1.8m.

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]

Veronicastrum virginicum 'Lavendelturm' (Culver's Root 'Lavendelturm'): Long, narrow spires of tiny, pale lavender-blue flowers above whorls of narrow, dark green, serrated leaves. Tall to up to 2m.