How to grow coast tea tree
Overview
Coast tea tree (Leptospermum laevigatum) is an evergreen tree or large shrub native to coastal eastern Australia, grown for its dense, grey-green foliage, windbreak and shade value, and its role in stabilising sandy soils. It produces small white flowers in spring, but its main landscape contribution is year-round structure and resilience.
Soil Preparation
Coast tea tree prefers slightly acidic to neutral soil (pH 5.5–7.0) that is free-draining. Sandy or sandy-loam soils are ideal; if your soil is heavy, improve drainage by mounding or adding coarse sand and gypsum. No additional fertiliser is needed at planting time—just a light native blend if soil is very poor.
Growing Guide
Plant coast tea tree in a position of full sun with well-drained, sandy or loamy soil. Space trees 2–3 m apart for a dense screen, or 4–5 m for a more open specimen. Dig a hole twice the width of the root ball, backfill with native soil, and water in well. Avoid heavy clay or waterlogged sites. Staking is only needed in very exposed positions; remove after one year.
Sowing
Sow seed in autumn (March–May) in a seed-raising mix, barely covering with fine sand. Keep moist and warm (20–25°C); germination takes 3–6 weeks. Transplant seedlings when 10–15 cm tall. Direct sowing is not recommended due to slow early growth and weed competition.
Care
Feed in early spring with a slow-release native fertiliser low in phosphorus. Prune lightly after flowering to shape and remove spent seed capsules; avoid heavy pruning into old wood. Mulch with organic matter (e.g., pine bark or compost) around the root zone to retain moisture in sandy soils, but keep mulch clear of the trunk.
Companion Planting
Pair with other coastal natives such as coastal banksia (Banksia integrifolia), pigface (Carpobrotus glaucescens), and saltbush (Atriplex nummularia) for a low-maintenance, wind-hardy screen. Avoid planting near moisture-loving plants like ferns or camellias, as they will compete poorly in the same dry, sandy conditions.
Common Pests & Risks
Scale insects and webbing caterpillars (e.g., leafroller) can attack coast tea tree. Control scale with a horticultural oil spray in late winter or early spring. For webbing caterpillars, hand-remove affected leaves or apply a Bacillus thuringiensis (Bt) spray. Monitor regularly, as infestations are usually localised.
Troubleshooting
Yellowing leaves: often caused by waterlogged soil or poor drainage—improve drainage or move to a mound. Brown leaf tips: wind scorch or salt spray in exposed coastal sites—provide a windbreak or screen. Sparse foliage: lack of sun or overcrowding—thin surrounding plants or prune to open canopy. Slow growth: heavy clay or compacted soil—amend with sand and organic matter before replanting. Leaf drop: sudden cold snap or frost—protect with shade cloth in cooler zones.