Caryopteris × clandonensis
- Herbaceous shrub, 2-3 ft (60-90 cm) tall, mounded. Leaves opposite, 10 cm long, lanceolate, gray-green to silvery above, gray-white below. Flowers bright blue, in clusters (cymes), in the axils of upper most leaves.
- Sun (best) or some shade; a preference for loamy, loose soil. Blooms in late summer to fall, attracts bees and butterflies.
- Hardy to USDA Zone 6 A cross of C. incana × C. mongholica raised, before 1933, by Arthur Simmonds, well regarded secretary of the Royal Horticultural Society. He is commemorated in 'Arthur Simmonds', which has been described as, "deservedly one of the most popular, small hybrid shrubs raised in this century" (20th century, England)(Hiller Manual, 1998). In the U.S. the more common cultivars include:
- 'Blue Mist': powder blue flowers
- 'Dark Knight': dark blue flowers and silver-gray leaves
- 'First Choice': cobalt-blue flowers, larger than most
- 'Longwood Blue': violet-blue flowers with silver-gray leaves
- 'Worcester Gold': smaller shrub, yellow foliage and lavender blue foliage
- Oregon State Univ. campus: on the north and south sides of the playground behind Bates Hall (i.e., east of Cordley Hall), cultivar Dark Knight.