This garden hybrid is a cross between two Chinese species, and is one of the best small shrubs for late colour in the border. It's hardier than often thought and will survive most winters unscathed. Growing Details Common Name: Caryopteris Genus: Caryopteris Species: x clandonensis Cultivar: 'Heavenly Blue' Skill Level: Beginner Exposure: Full sun Hardiness: Hardy Soil type: Well-drained/light, Moist Height: 90cm Spread: 150cm Description Any damage to shoots is removed by hard annual pruning, which keeps plants flowering prolifically and prevents a bare base from developing. The bushes are dome-shaped, with new stems arching gracefully under the weight of the dense, deep blue flower clusters, which stand out well against the soft green foliage. The Royal Horticultural Society has given it its Award of Garden Merit (AGM).