Caryopteris × clandonensis

Tolerant of dry soil, but prefers well-drained soils in full sun.

Caryopteris × clandonensis ‘Blue Empire’ PP30494 has a motto of big, blue, and beautiful! We found that to be true in our own trial gardens here at North Creek. Its powdery grey-green foliage is the perfect skirting to present the long wands of stacked deep blue flowers. The flowers are bigger than other Caryopteris that we have trialed with long wands lasting weeks on end. It is a wonderful addition to the landscape or container garden as well as an excellent choice for cut flowers. It has a superior low growing habit and late season bloom attracting pollinators from miles around. It grows 40” tall and 30” wide with profusions of flowers.

Caryopteris × clandonensis is a hybrid between two Asiatic species of C. incana and C. mongholica, originating from the Himalayas and East Asia. An easy to grow plant that prefers full sun in average, well-draining soil, Caryopteris can tolerate periods of drought and may experience crown rot if allowed to sit in water-logged soil. In colder zones, bluebeard should be given a hard prune in late spring as tips will experience winter dieback. Blooms occur on new wood and hard pruning doesn’t affect bud set. Considered a subshrub with herbaceous stems coming from woody center, roots are hardy to zone 5 while branches are hardy to zone 7.

We love Caryopteris because of its performance in leaner, drier soils and are happy to use them en masse in the garden for late season impact or in a container as a formal statement piece. It is extremely resistant to herbivory by deer and rabbits due to its fragrant foliage. ‘Blue Empire’ has superior disease resistance and was introduced by Boomkwekerij Elst-van Bergen in the Netherlands.