This rounded, deciduous shrub is a hybrid between two Asian Caryopteris species. Long, narrow grey-green aromatic leaves serve as an effective backdrop for the blue flowers. This summer bloomer produces whorls of deep blue, nectar-rich flowers that attract bees and butterflies. The flowers turn into attractive dried seed heads in the fall and winter. Plant in full sun or part shade, well-drained soils, and provide supplemental summer water. Prune back hard in the winter. It is said to be deer-resistant.