How to Grow Bluebeard
Caryopteris x clandonensis
Caryopteris is a compact, late-flowering shrub producing clusters of intense blue flowers from August to October when little else is in bloom. Plant in full sun in light, well-drained soil — it thrives in poor, dry conditions and is excellent for pollinators. Prune hard to a low framework in mid-spring. The aromatic grey-green foliage is a bonus.
Yearly Lifecycle
Care Essentials
Minimal feeding needed. A light dressing of general fertilizer in spring is sufficient. Avoid rich soil which produces leggy growth at the expense of flowers.
Watch For
- Winter dieback in cold, wet soils
- Capsid bugs distorting shoot tips
- Root rot in waterlogged ground
Care Requirements
Light
Full sun
Needs good drainage and heat to flower well. A south-facing border or gravel garden is ideal. Will not thrive in shade.
Watering
Drought-tolerant
Avoid overwatering especially in winter. Established plants thrive on neglect. Excess moisture is the main killer.
Fertilizing
Minimal
Light general fertiliser in spring only. Rich soil reduces flowering. On poor soils no feeding is needed at all.
Pruning
Hard prune to 15-30 cm each mid-April
Flowers on new growth so hard annual pruning is essential. Cut all stems back to a low framework of buds in mid-April.
Overwintering
Hardy to about -15C
Ensure free-draining soil to prevent winter losses from root rot. On heavy soil, add grit at planting. No other protection needed.
Growing Tips
Thrives in poor dry soil — avoid rich soil
Caryopteris flowers best when slightly starved. Rich soil produces lush foliage at the expense of the blue flowers it is grown for.
Outstanding late-season pollinator
One of the best plants for bees and butterflies in August and September when few other shrubs are flowering.
Prune hard in mid-April every year
Cut all growth back to 15-30 cm each mid-April. Without this annual hard prune, the plant becomes leggy and flowers poorly.
Pests & Diseases
Pest Capsid Bug
Identification: Ragged holes and distorted shoot tips; damage appears before the insect is seen
- Difficult to control organically; remove damaged shoots; encourage \ natural predators
- Spray with contact insecticide containing deltamethrin when damage first appears
Pest Aphids
Identification: Clusters of green or black insects on soft new growth; distorted shoot tips
- Squash by hand or blast with water; encourage ladybirds
- Spray with pyrethrin-based contact insecticide
Disease Root Rot Phytophthora cinnamomi
Symptoms: Sudden wilting and collapse, especially in winter or wet spring; brown rotted roots
Treatment: No cure once established; remove and destroy affected plants; improve drainage before replanting
Prevention: Ensure free-draining soil; never mulch tightly against the crown; avoid overwatering
Disease Powdery Mildew Erysiphe sp.
Symptoms: White powdery coating on leaves in late summer; premature leaf drop
Treatment: Spray with sulphur-based fungicide or potassium bicarbonate
Prevention: Ensure good air circulation; avoid drought stress which weakens defences
