What are the watering needs of Grevillea robusta?
Young trees need regular watering until established. Mature trees are drought-tolerant, requiring supplemental watering only during prolonged dry periods.
Silk Oak (Grevillea robusta)
Silk Oak (Grevillea robusta) is a fast-growing Australian native tree with striking golden-orange flowers, fern-like foliage, and a dense canopy.
Above information is sourced from Wikipedia
Sunlight
Full Sun
Watering
Moderate
Soil
Well-drained
Temperature
Moderate
Fertilizer
Low
Care Requirements
Light
Full Sun
Prefers full sun for best flowering and growth.
Water
Moderate
Water young plants regularly; established trees are drought-tolerant.
Soil
Well-drained
Temperature
Moderate
Prefers warm temperatures; protect from frost when young.
Fertilizer
Low
Feed young plants sparingly; mature trees rarely need it.
Plant Overview
Plant Type
Tree
Plant Category
Ornamental
Plant Place Type
Garden
Lifespan
Perennial
Plant Height
15-30 m
Spread
8-15 m
Growth Rate
Fast
Dormancy
Evergreen
Leaf Color
Green, Silver
Leaf Type
Fern-like
Flower Size
1.5-2 cm
Optimal Sunlight Lux
60000
Image Gallery
Flowering & Fruiting Cycles
Monthly activity intensity for bloom and fruit across both hemispheres.
Northern hemisphere
Flowering & fruiting calendar
Peak bloom · JunPeak fruit · Mar
FloweringFruiting
Southern hemisphere
Flowering & fruiting calendar
Peak bloom · AugPeak fruit · Sep
FloweringFruiting
Synonyms
Grevillea umbratica A.Cunn. ex Meisn.
Grevillea venusta A.Cunn. ex Meisn.
Stylurus robustus (A.Cunn. ex R.Br.) O.Deg.
Taxonomy
- kingdomPlantae
- divisionTracheophyta
- classMagnoliopsida
- orderProteales
- familyProteaceae
- genusGrevillea
- speciesGrevillea robusta
Toxicity
Toxic for humans
No
Rating: 0/5
Toxic for pets
No
Rating: 0/5
Sap can cause contact dermatitis in humans. Wood dust can cause respiratory irritation. All parts are considered toxic to pets, potentially causing gastrointestinal upset.
Additional Care Tips
Water young Grevillea robusta regularly, keeping the soil consistently moist but not waterlogged. Mature trees are quite drought-tolerant once established and require less frequent watering, only during prolonged dry spells. Allow the top few centimeters of soil to dry out between waterings for optimal health.
Prune Grevillea robusta to shape the tree, remove dead or crossing branches, and control its size. Heavy pruning can be done after flowering to encourage denser growth. Avoid pruning too late in the season to allow new growth to harden off before winter.
Grevillea robusta can be propagated from seeds sown in spring or from semi-hardwood cuttings taken in summer. Seeds require scarification or soaking before sowing. Cuttings should be treated with rooting hormone and placed in a well-draining medium.
Repot young silk oaks every 1-2 years into slightly larger containers as needed, preferably in spring. Ensure the new pot has adequate drainage. Mature trees are best left in their pots or planted out, as they dislike root disturbance.
FAQs
What type of soil does Silk Oak prefer?
It prefers well-drained soil. It can tolerate a range of soil types, including sandy, loamy, and clay soils, but good drainage is crucial.
Is Grevillea robusta suitable for small gardens?
Due to its potential size, Grevillea robusta is generally not recommended for small gardens. It thrives in larger spaces where it has room to grow.
Does Silk Oak attract wildlife?
Yes, the nectar-rich flowers attract birds, particularly nectar-feeding birds like honeyeaters, and also insects.
How should Grevillea robusta be pruned?
Pruning can be done to shape the tree or remove dead or damaged branches. Light pruning is usually sufficient; heavy pruning can be done after flowering.