Grevillea Superb

Sun

Full sun for the best flowering; tolerates light partial shade.

Water

Water regularly while establishing, then deeply during prolonged dry spells. Let the soil drain and partly dry between waterings; avoid persistently wet roots.

Soil

Well-drained, low-phosphorus soil, preferably slightly acidic to neutral. Sandy or gravelly soil suits it; improve drainage with a raised bed where soil is heavy.

Height

5-8 ft (1.5-2.4 m)

Spread

6-10 ft (1.8-3 m)

Flowers

Coral-orange to salmon flower clusters with yellow and cream tips, appearing through much of the year in warm climates; flowering slows in cold weather.

Foliage

Evergreen. Deeply divided, fern-like green leaves with paler undersides.

Growth

Moderate to fast in warm conditions.

Care needed

Medium

• Pollinators
• Drought tolerant
• Heat tolerant
• Wildlife
• Low allergen

Northern hemisphere months. In Australia, shift them by six.

Difficulty

Hard

Toughness

Needs looking after

Pick your zone, country, light and whether you have pets.

1. Planting day

   1.6 ft (0.5 m)

2. After 1 year

   2.8 ft (0.86 m)

3. After 2 years

   4 ft (1.2 m)

4. After 3 years

   5 ft (1.6 m)

5. After 5 years

   6 ft (2 m)

   full size

About 4 years to full size.

From a typical nursery size, at an average rate for this kind of plant. A rule of thumb, not a forecast.

Cats and dogs

Safe

Growth rate

Fast

• Water the root zone deeply during the first growing season, allowing excess water to drain away.
• Use only a low-phosphorus fertiliser labelled for Australian native plants, and feed lightly in spring if needed.
• Apply a loose organic mulch, keeping it clear of the stems.
• Avoid manure-rich compost and standard high-phosphorus flowering feeds.
• In colder regions, grow in a large container of free-draining, low-phosphorus potting mix and overwinter in a bright, frost-free place.

Pruning. Tip-prune young shoots to build a bushy framework, then lightly shorten leafy stems after a main flush of flowers in spring or summer. Avoid cutting hard into old, bare wood, and wear gloves because grevilleas can irritate skin.

Spring

Plant once damaging frosts have passed, choosing a sunny position with excellent drainage.

Spring

Apply a light dose of low-phosphorus native-plant fertiliser if growth is weak.

Late spring

Lightly trim leafy growth after a flowering flush to maintain a dense shape.

Summer

Water newly planted shrubs deeply during dry weather; check containers more often.

Late summer

Take semi-ripe cuttings from healthy, non-flowering shoots.

Autumn

Check drainage before wetter weather and move container plants under cover where frost is likely.

Winter

Protect from frost and keep sheltered container plants on the dry side without letting the root ball dry out completely.

• Use as a flowering specimen in a sunny Australian-native border, with room for its spreading branches.
• Plant as an informal screen where frequent clipping is unnecessary.
• Combine with lomandra and kangaroo paws for contrasting leaf shapes and warm flower colours.
• Grow in a large courtyard container where it can receive winter protection.
• Place near a seating area to watch nectar-feeding birds, but keep branches away from narrow paths.

Garden styles it suits: Australian native, Wildlife garden, Mediterranean, Coastal, Dry gravel garden and Modern courtyard.

Plant it with: Lomandra, Kangaroo paw, Westringia, Dianella and Waxflower.

Wildlife: Flowers provide nectar for honeyeaters in Australia and hummingbirds where these occur in North America. Bees and other insects also visit the flowers, and the branching growth offers cover for small birds.

• Root rot in wet soil: improve drainage, avoid frequent shallow watering and do not leave containers standing in saucers of water.
• Phosphorus injury, showing as yellowing, scorched leaves or decline: stop unsuitable fertilisers and use only low-phosphorus native-plant products.
• Frost damage to leaves and shoot tips: provide shelter or frost cloth and wait until spring growth begins before trimming damaged stems.
• Scale insects: inspect stems and leaf undersides, prune badly infested shoots and use a labelled horticultural oil if necessary, avoiding hot weather.

Not known to cause systemic poisoning in cats, dogs or horses, but cultivar-specific information is limited. Leaves, stems and flowers can cause contact dermatitis in susceptible people; related grevillea hybrids are well known for this. Wear gloves when pruning, and do not treat the flowers or nectar as human food.

• Robyn Gordon grevillea (Grevillea 'Robyn Gordon')

  Has a similar rounded habit and divided foliage, but its flowers are predominantly red rather than the coral-orange, yellow and cream blend of 'Superb'.

• Scarlet grevillea (Grevillea banksii)

  Usually has leaves divided into fewer, longer, narrow lobes with conspicuously pale undersides. Its flower forms are generally red or cream rather than the mixed orange tones of 'Superb'.

Grevillea honours Charles Francis Greville, a British plant collector and patron of botany.

Propagation. Take semi-ripe cuttings in late summer and root them in a free-draining propagation mix with gentle bottom heat. Cuttings preserve the cultivar; seedlings, if produced, will not reliably come true.

Accepted botanical name

Grevillea

Sources: GBIF (CC BY 4.0). The care and design notes are LandscapeGPT's own.