How to grow oleander
Overview
Oleander (Nerium oleander) is a dense, evergreen shrub grown for its long-lasting clusters of pink, white, or red flowers and its ability to provide structure in hot, dry gardens. It thrives in full sun and poor soils, but all parts are highly toxic if ingested, requiring careful handling.
Varieties
- Nerium oleander 'Petite Pink' — A compact, dwarf variety reaching 1–1.5 m, ideal for small gardens or containers in Australian conditions.
- Nerium oleander 'Splendens' — A vigorous, double-flowered form with deep pink blooms, popular for hedging in warm zones.
- Nerium oleander 'Luteum Plenum' — A rare double yellow-flowered cultivar, prized for its unusual colour in subtropical gardens.
Soil Preparation
Oleander tolerates a wide range of soils but prefers a neutral to slightly alkaline pH (6.5–7.5). Improve drainage in heavy clay by adding gypsum or planting on a mound. It thrives in poor, sandy soils and does not need rich amendments.
Growing Guide
Plant oleander in a position that receives at least 6 hours of direct sun daily, in well-drained soil. Space plants 1–2 m apart for hedges or 3 m for specimens. Dig a hole twice the width of the root ball, backfill with native soil, and water in deeply. Avoid overwatering; once established, water only during extended dry spells. Prune in late winter or after flowering to maintain shape and remove dead wood.
Care
Feed in early spring with a slow-release fertiliser for flowering shrubs. Prune after the main flowering flush to remove spent blooms and shape the plant, always wearing gloves and long sleeves. Mulch with organic material to retain moisture and suppress weeds in hot sites.
Companion Planting
Oleander pairs well with other drought-tolerant plants like bougainvillea, lantana, and rosemary. Avoid planting near edible gardens or water features where fallen leaves could contaminate. It is also a useful windbreak in coastal sites.
Common Pests & Risks
Oleander is prone to oleander scale (small white or brown bumps on stems), aphids on new growth, and caterpillars that skeletonise leaves. Control scale with horticultural oil in winter, and treat aphids with a strong water spray or insecticidal soap. Caterpillars can be hand-picked or controlled with Bacillus thuringiensis.
Troubleshooting
Yellow leaves: often caused by overwatering or poor drainage; reduce water and improve soil. Brown leaf tips: usually from salt build-up or wind scorch; flush soil with water and shelter from strong winds. Stunted growth: may indicate root rot from waterlogged soil; check drainage and avoid planting in low spots. Sparse flowering: insufficient sun or over-pruning; ensure full sun and prune only after bloom. Leaf drop: cold damage in temperate zones; protect with frost cloth or plant in a warm microclimate.