Acacia leiocalyx
black wattle
Overview
Acacia leiocalyx is an evergreen shrub to small tree growing 3-8 m (10-26 ft) tall and 2-4 m (6.5-13 ft) wide, native to eastern Australia. Mature plants bear flattened leaf-like phyllodes rather than true leaves; these are curved or sickle-shaped, 6-15 cm (2.4-5.9 in) long, with several prominent longitudinal veins and a slightly sticky surface when young. The branchlets are distinctly angled or winged, a useful field character. From late autumn into spring the plant carries many bright golden-yellow cylindrical flower spikes 2-5 cm (0.8-2 in) long among the phyllodes, followed by twisted or coiled brown pods holding hard seeds. It is a fast-growing pioneer of disturbed ground, road batters, and forest margins on sandy or gravelly soils, and fixes nitrogen through root nodules. The species tolerates poor soil, wind, and dry spells once established. Like most short-lived wattles it is comparatively brief, often living only 10-15 years, and can self-seed freely into open ground, so it spreads beyond where it is planted in warm districts.
Native Range
Native to eastern Australia, mainly Queensland and north-eastern New South Wales, growing in eucalypt forest and woodland, on coastal sand, and along disturbed ground and watercourses on a range of light soils.Suggested Uses
Used in revegetation, erosion control on banks and batters, windbreaks, and habitat plantings on poor soils. The early flowers support bees and other insects in the cooler months. Spaced 2-3 m (6.5-10 ft) apart in screens and shelterbelts.How to Identify
Appearance
Size & Dimensions
Height10' - 26'3"
Width/Spread6'7" - 13'1"
Reaches mature size in approximately 5 years
Bloom Information
Flowers from late autumn through spring, roughly June to September, earlier than many wattles, with golden-yellow cylindrical spikes crowded along the stems. The display lasts several weeks. Coiled pods ripen over the following months and split to shed hard seeds.
Detailed Descriptions
Foliage Description
greenGrowing Conditions
Sun Requirements
Requires 6-9 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
Grow in full sun on light, well-drained sandy or gravelly soil, including poor and disturbed ground. Water through the first season to establish, after which the plant draws on deep roots and tolerates dry conditions. High-phosphorus fertiliser harms wattles adapted to lean soils, so use low-phosphorus native blends only. A light trim after flowering keeps growth dense and reduces legginess. The species grows fast and lives only 10-15 years, and seed can germinate after fire or disturbance, so seedlings may appear in surrounding ground. It withstands light frost but is damaged by hard freezes when young.Pruning
Tip prune from an early age and lightly after flowering to build a denser, well-branched framework. Plants grown as small trees can be raised on a single trunk by removing low side branches while young. Old, sparse specimens respond poorly to hard cutting and are usually replaced.Pruning Schedule
J
F
M
A
M
J
J
A
S
O
N
D
spring
Container Growing
✓ Suitable for container growing
Minimum container size: 7 gallons