Leucanthemum x superbum 'Wirral Supreme':
Tall form of Shasta daisy with white flowers and multiple shorter petals around the golden centre, making an attractive frilly effect. Hardy. Up to 1.5m.
Liatris spicata 'Alba':
Spikes of white flowers in mid to late summer. Very useful vertical accent. Bees adore it. To 80cm. Hardy