Asian natives valued for their contribution of cool blue to flower borders from midsummer to frost. Bear dense stalked clusters of small flowers on current season’s growth. Erect form. Leaves and flowers are aromatic.
Generally grown as woody-based perennials: if plants don’t freeze back in winter, cut them nearly to the ground before spring growth flush to ensure a good base for the new season’s growth. Trim after each wave of bloom to encourage repeat flowering. Provide good drainage, since plants can rot in wet soil.
Somewhat loose, open growth to 3–4 ft. tall, 5 ft. wide. Oval, pointed leaves have toothed margins. Lavender-blue flowers appear in leaf joints on upper part of stems.
Low-growing mound (to 2 ft. tall and wide) of narrow, 3-in.-long leaves. Clusters of small blue flowers top upper parts of stems.
All bear single flowers with a prominent sunburst of stamens in the center. Shallowly cup-shaped,...
These annual and perennial plants are grown as herbal remedies and for culinary use.