Baptisia 'Purple Smoke' (Indigo weed 'Purple Smoke'): Tall spikes of violet pea-like flowers on almost black stems, attractive grey-green foliage. Dark-grey seed pods. Hardy. Up to 1.2m

Echinacea purpurea 'Green Twister' (Coneflower 'Green Twister'): A new variety with a unusual mix of purple and lime green flowers with upturned petals and a central dark cone. Hardy. Up to 60cm.

Heuchera 'Midnight Rose': Darkest purple leaves, splashed with bright pink. Excellent for all year round foliage colour. Hardy. Up to 30cm.

Pulsatilla vulgaris 'Papageno' (Pasque flower 'Papageno'): The petals are deeply dissected, giving a frilled, double effect. Usually purple but can be pink, reddish or white. Hardy. To 30cm

Salvia x jamensis 'Nachtvlinder' (Sage 'Nachtvlinder'): Regal purple flowers on upright stems throughout late summer into autumn. [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 [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. [Collect Only]