Campanula lactiflora 'Alba' (Milky bellflower 'Alba'): Tall stems with clusters of pure white flowers in mid-summer. Ideal for filling out borders and adding height. Hardy. Up to 1.2m

Lysimachia clethroides (Gooseneck Loosestrife): Spikes of white flowers arch over and tip up again, like a goose or swan neck. To 1m. Hardy