Illawarra flame tree

Sun

Full sun for the best flowering; tolerates light shade.

Water

Water regularly while establishing. Established trees tolerate seasonal drought, but benefit from deep watering during prolonged dry weather.

Soil

Well-drained soil, including loam, sand or clay that does not remain waterlogged; mildly acidic to mildly alkaline conditions.

Height

30-60 ft (9-18 m) in gardens; potentially taller in favourable climates.

Spread

20-40 ft (6-12 m)

Flowers

Late spring to early summer; bright scarlet-red, waxy, bell-shaped flowers in large clusters. Flowering may be partial or absent in some years.

Foliage

Large, glossy green leaves, variable in shape, often with three to seven lobes. Deciduous to semi-evergreen depending on climate; leaf fall commonly precedes flowering.

Growth

Moderate to fast in warm conditions with adequate moisture.

Care needed

Medium

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

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

Difficulty

Hard

Toughness

Fairly tough

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

1. Planting day

   7 ft (2 m)

2. After 1 year

   9 ft (2.7 m)

3. After 2 years

   11 ft (3.4 m)

4. After 3 years

   14 ft (4.2 m)

5. After 5 years

   18 ft (5.6 m)

About 16 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

Mildly toxic: may upset a stomach

Native to

Australia

Growth rate

Fast

• Plant where the mature crown and roots have ample space, away from buildings, drains and paving.
• Water deeply through the first two growing seasons, allowing the surface soil to dry between waterings.
• Spread organic mulch over the root zone, keeping it clear of the trunk.
• Feed lightly in spring only if growth is weak or the soil is poor; avoid excessive nitrogen.
• Stake only if necessary in an exposed position, and remove supports once the roots hold the tree firmly.

Pruning. Train young trees to a strong central leader, removing competing leaders and poorly attached branches while they are small. Prune lightly after flowering in warm weather; avoid topping or heavy cutting, and use a qualified arborist for large limbs.

Spring

Plant after frost risk has passed, and begin regular deep watering for newly planted trees.

Spring

Refresh mulch and check young trees for competing leaders or rubbing branches.

Late spring

Expect possible leaf drop before flowering; check soil moisture before assuming the tree needs more water.

Summer

Water young trees during dry spells and established trees during prolonged drought.

After flowering

Remove dead or damaged small branches and make any necessary light formative cuts.

Autumn

Collect fallen pods with gloves and check that winter rain can drain freely from the root zone.

• Use as a flowering specimen in a large lawn, where its full crown can develop.
• Pair with jacaranda for contrasting red and violet flowers where their flowering seasons overlap.
• Set above low, drought-tolerant planting so the trunk and seasonal flower display remain visible.
• Use in a spacious Australian native garden with grasses and tough, low shrubs.

Garden styles it suits: Australian native, Architectural minimal, Modern tropical, Mediterranean, Grand estate and Hot border.

Plant it with: Jacaranda, Kangaroo paw, Mat rush, Coastal rosemary and Bird of paradise.

Wildlife: Flowers provide food for nectar-feeding birds and insects, while the crown offers shelter and perching sites.

• Frost damage: young growth and young trees are vulnerable; choose a sheltered, frost-free position and protect small trees during unexpected cold.
• Root decline in waterlogged soil: improve drainage before planting and avoid frequent shallow irrigation.
• Scale insects and associated sooty mould: inspect stems and leaf undersides, control ants, and treat accessible infestations with a labelled horticultural oil.
• Little or no flowering: juvenile trees may take many years to bloom, and mature trees do not flower heavily every year; provide full sun and avoid excessive nitrogen or severe pruning.

Raw seeds are reported to be poisonous to people and should not be eaten. The pods contain stiff hairs that can irritate skin and eyes; wear gloves when handling them. Toxicity to cats, dogs and horses is not well documented, so prevent animals from chewing pods or seeds.

• Kurrajong (Brachychiton populneus)

  Usually has smaller, less deeply lobed leaves and cream to pinkish bell-shaped flowers, often spotted inside, rather than masses of scarlet flowers.

• Lacebark tree (Brachychiton discolor)

  Has larger pink flowers and leaves with distinctly pale, felted undersides; flame tree leaves are comparatively smooth and glossy.

• Royal poinciana (Delonix regia)

  Also called flame tree, but has finely divided, fern-like leaves, broad open flowers and long, flat seed pods.

Illawarra refers to the coastal region of New South Wales, while acerifolius means maple-leaved, describing the lobed foliage.

Propagation. Usually grown from seed sown in warmth in a free-draining seed mix. Carefully remove the seeds from the hairy pods while wearing gloves and eye protection; soaking seeds in warm water before sowing can help germination.

Accepted botanical name

Brachychiton acerifolius

Native range

New South Wales and Queensland.

Measured

Average height 1800 cm.

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