How to grow bougainvillea
Overview
Bougainvillea is a vigorous, thorny climbing vine prized for its vibrant, papery bracts that surround small white flowers. It is commonly used to cover walls, fences, and pergolas, adding a dramatic splash of colour. Key to success is full sun, excellent drainage, and keeping the plant on the dry side – overwatering will suppress blooms.
Varieties
- Barbara Karst — Vigorous variety with large clusters of bright magenta-red bracts, ideal for quick coverage.
- Golden Glow — Rare yellow-bracted cultivar that holds its colour well in full sun.
- Pink Pixie — Compact dwarf form, perfect for pots or small gardens, with deep pink bracts.
- Raspberry Ice — Variegated cream and green foliage with raspberry-red bracts; good for containers.
Soil Preparation
Bougainvillea prefers slightly acidic to neutral soil (pH 5.5–7.0) with excellent drainage. A sandy loam or loam enriched with coarse sand and organic matter works well. Avoid heavy clay unless mounded; add gypsum to improve structure. Poor soil actually encourages more blooms – do not over-fertilise.
Growing Guide
Plant bougainvillea in a hole twice the width of the root ball and at the same depth. Space vigorous varieties 2–3 m apart along fences. Use a free-draining mix; if soil is heavy, raise the planting mound. Water in well, then reduce to a deep soak every 7–10 days once established. Train young stems onto supports with soft ties. In cooler temperate areas, choose a north- or west-facing wall for extra warmth.
Care
Apply a low-nitrogen, high-potassium fertiliser (e.g. 2:3:4 or rose food) in early spring and again in summer to encourage blooming. Prune after each flowering flush to shape and remove dead wood – always wear thick gloves against thorns. Mulch with gravel or pebbles to keep roots warm and reduce competition.
Companion Planting
Bougainvillea pairs well with other sun-loving, drought-tolerant plants such as lantana, plumbago, and geraniums. Avoid planting species that require frequent watering or deep shade, such as ferns or hostas, as this will conflict with the bougainvillea's dry requirements.
Common Pests & Risks
Scale insects and mealybugs are common, appearing as sticky honeydew and sooty mould. Treat immediately with horticultural oil or neem oil. Caterpillars (especially bougainvillea looper) can chew leaves; hand-pick or spray with Bacillus thuringiensis. Check regularly, as heavy infestations can weaken the plant.
Troubleshooting
Yellow leaves and leaf drop: usually overwatering or poor drainage – let soil dry out and improve drainage. No blooms: results from too much nitrogen or insufficient sun – stop feeding high-N fertiliser and ensure 6+ hours direct sun. Brown leaf edges: salt buildup or wind burn – flush soil and provide wind shelter. White sticky spots on stems: scale insect – treat with horticultural oil. Sparse foliage and leggy growth: lack of pruning – cut back hard after flowering to encourage bushy re-growth.