Cynara cardunculus (Cardoon): Dramatic, tall silver leaved plant topped with large purple thistle flowers in mid-summer. Hardy. Up to 2.5m.

Veronicastrum virginicum 'Apollo' (Culver's Root 'Apollo'): Very long, narrow spires of pale purple blue flowers above whorls of narrow, dark green, serrated leaves. To 1.5m. 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. [Collect Only]