Growing Guide
Plant grevilleas in autumn (March to May) or spring (September to November) to allow roots to establish before extreme heat or cold arrives. Avoid planting in the peak of summer heat in arid or subtropical regions. Prepare planting sites with excellent drainage — grevilleas are highly susceptible to root rot in waterlogged conditions. Dig in coarse sand or fine gravel if your soil is heavy clay, and avoid adding compost or organic matter excessively, as rich soils can cause problems. Plant at the same depth as the nursery pot and water in gently with a diluted seaweed solution to reduce transplant stress. Water regularly for the first two to three months until the plant is established, then reduce to occasional deep watering during prolonged dry spells — mature grevilleas are remarkably drought tolerant. Avoid overhead watering, which can encourage fungal issues on foliage. Feed sparingly in spring with a slow-release native fertiliser formulated for phosphorus-sensitive plants. Avoid fertilisers high in phosphorus, which are toxic to most proteaceous plants including grevilleas. Mulch around the root zone with a 5–7 cm layer of coarse organic mulch, keeping it clear of the main stem. Deadheading spent flower clusters can encourage continued blooming and keeps the plant looking tidy through the growing season.
🤝 Good Companions
Grevilleas pair beautifully with other Australian natives such as kangaroo paw (Anigozanthos)
westringia
and lomandra
which share the same preference for free-draining
low-phosphorus soils and together create a cohesive
wildlife-friendly planting. Callistemon (bottlebrush) makes an excellent companion
attracting the same honeyeater species and thriving under similar low-water
full-sun conditions.
❌ Avoid Planting With
Avoid planting grevilleas near roses
camellias
or other garden plants that require regular phosphorus-rich fertilisers
as fertiliser runoff can cause fatal nutrient toxicity in grevilleas. Vegetables requiring frequent composting and rich soil amendments are also poor neighbours
as the enriched growing conditions are directly at odds with grevillea's needs.
🐛 Pests & Diseases
Grevilleas can occasionally be affected by scale insects and sooty mould, which can be treated organically by wiping affected stems with diluted neem oil or horticultural soap spray. Phytophthora root rot is the most serious threat, caused by poorly drained soils — prevention through excellent drainage is far more effective than any cure. Grevillea looper caterpillars may defoliate plants periodically but healthy, established specimens typically recover without intervention.
🌱 Fertilising
Feed grevilleas once in spring with a slow-release native plant fertiliser that is specifically low in phosphorus, such as Osmocote Native Gardens or a dedicated proteaceous plant formula. Avoid standard garden fertilisers entirely, as even moderate phosphorus levels can cause rapid decline and death in these phosphorus-sensitive plants.
✂️ Pruning & Training
Prune grevilleas lightly after the main flowering flush, trimming back by up to one-third to encourage bushy, compact growth and stimulate another round of blooms. Always prune into leafy green growth rather than cutting back to bare wood, as most grevillea species do not regenerate reliably from old, leafless stems.
🔬 Propagation
Grevilleas are most reliably propagated from semi-hardwood tip cuttings taken in late summer to autumn, treated with rooting hormone and struck in a free-draining propagating mix of coarse sand and perlite. Seed propagation is possible but can be slow and variable, with fresh seed giving the best germination rates after light scarification or a brief soak in warm water.