Brachychiton rupestris
Queensland bottle tree
Overview
Brachychiton rupestris is a slow-growing tree reaching 30-60 feet (10-18 m) tall, recognised by a trunk that swells with age into a bottle or flask shape up to 6-12 feet (1.8-3.5 m) across at the base. The swollen trunk stores water and is most pronounced on mature trees, while young plants are slender and unbranched. The canopy is fairly open and rounded. Leaves vary from simple and narrow to deeply divided into five to nine narrow lobes, 2-4 inches (5-10 cm) long, glossy green. The tree drops most of its leaves for a short period in spring before flowering. Bell-shaped cream flowers about 0.5 inch (12 mm) long, spotted inside, appear in spring and early summer. They are followed by woody, boat-shaped pods 1-3 inches (2.5-7.5 cm) long holding yellow seeds surrounded by irritant hairs. B. rupestris is native to inland Queensland, where it grows in dry brigalow and bottle-tree scrub on clay and rocky soils. It withstands long dry spells and light frost once established. Growth is slow, and the swollen trunk develops only over many years, so young trees show little of the mature form.
Native Range
Brachychiton rupestris is native to inland central and southern Queensland, Australia, where it grows in dry brigalow scrub and on stony ridges. It is most common on clay and rocky soils in semi-arid country.Suggested Uses
Brachychiton rupestris is planted as a feature and shade tree in parks, large gardens, and streetscapes in warm, dry climates, and is grown for many years as a container and bonsai subject. Its drought tolerance suits low-water and inland plantings.How to Identify
Appearance
Size & Dimensions
Height30' - 60'
Width/Spread15' - 30'
Reaches mature size in approximately 20 years
Bloom Information
Bell-shaped cream flowers open in spring and early summer, roughly September to December in Australia, often after the tree has shed much of its foliage. Flowering varies from year to year and can be sparse in dry seasons. Woody pods follow and ripen over the following months.
Detailed Descriptions
Foliage Description
glossy greenGrowing Conditions
Sun Requirements
Requires 6-10 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight
Care & Maintenance
Care Guide
Brachychiton rupestris grows in full sun on free-draining clay, loam, or rocky soils and tolerates extended drought once the trunk has begun to thicken. Young trees grow slowly and benefit from regular water in their first few seasons, after which established trees need little irrigation. It withstands light to moderate frost in USDA zones 9-11. The species transplants well even as a large tree because of the water stored in its trunk. Growth in cultivation is slow, with the bottle shape taking decades to develop. It grows well in containers for many years before being planted out.Pruning
Little pruning is needed beyond removing dead or crossing branches to build a clear trunk on young trees. Lower limbs can be lifted over several years to expose the swollen trunk. The species reshoots readily from pruning cuts.Pruning Schedule
J
F
M
A
M
J
J
A
S
O
N
D
winter
Container Growing
✓ Suitable for container growing
Minimum container size: 15 gallons