Kangaroo Thorn

Kangaroo Thorn (Acacia paradoxa) is the native shrub to plant where you want a barrier nothing walks through. It grows fast to around 2.5m tall and wide, building a dense tangle of wavy foliage armed with sharp spines at every leaf node, then covers itself in golden ball flowers in late winter and spring. Small birds nest inside it because larger predators cannot follow.

Why you'll love it

• A genuine security hedge. The spines deter people and animals along a boundary without a fence.
• Fast to close up. A young row reads as a solid thicket within two seasons.
• Refuge for small birds. Wrens and finches nest in the thorny interior, and the blossom draws bees and butterflies.
• Handles the hard sites. Frost hardy, drought tolerant, wind tolerant, salt tolerant and content in poor soil.

Where it works best

Screening and hedging. Plant 1.5m apart in a single row for a dense prickly barrier. Keep it well back from paths and play areas, because the spines are sharp enough to draw blood.

Windbreak. A staggered double row at 1.5m spacing filters wind across an exposed paddock or coastal block and shelters the planting behind it.

Mass planting. On a difficult bank or a rough boundary strip it covers ground and suppresses weeds with almost no input.

Growing kangaroo thorn in Australia

Position and climate. Full sun gives the densest, spiniest growth, though it accepts part shade. It suits warm temperate, cool temperate, Mediterranean and arid gardens, and being frost hardy it holds up in cold inland districts. Before planting, check with your local council, because it is known to naturalise outside its home range and is regulated in some areas.

Soil. Any reasonably drained soil, including gravelly and poor ground. Like most wattles it dislikes wet feet, so keep it out of soggy corners.

Water and feed. Deep watering once a week through the first summer settles the roots, after which it needs little more than seasonal rain. Feeding is rarely necessary, and a low phosphorus native blend is the only safe choice.

Pruning. Tip prune from young to build density, then trim lightly after flowering, wearing thick gloves and eye protection. It reshoots from light trimming but will not always recover from a hard cut into bare wood.

What to expect when it arrives

It is grown as tube stock, in a 140mm pack of ten and a 200mm pack of six. Tubes suit a long boundary because wattles establish quickly from small sizes, while the 140mm and 200mm packs give a head start on a shorter run. Plants arrive with spines already formed, so handle the boxes with gloves.

Plants are packed to travel upright and delivered Australia wide, with delivery from $29.95. Expect a slow first month, then rapid growth through the first warm season, backed by our 30 day healthy plant guarantee.

Plant care guides and related reading

• How to grow and care for acacias
• Browse Australian native shrubs
• Compare plants for windbreaks
• Hedging and screening options

Common questions

How far apart should I plant it for a hedge?

One and a half metres apart in a single row. That lets each plant reach its full 2.5m width and knit into its neighbours without crowding the bases.

How prickly is it, really?

Very. The spines are rigid and sharp, which is the point of the plant, so it is a poor choice beside a footpath or a play space. Gloves and long sleeves are essential for trimming.

Can I plant it anywhere in Australia?

Not necessarily. It naturalises readily outside its native range and is restricted in parts of the country, so confirm with your local council before ordering for a rural boundary.

When does it flower?

Golden ball flowers appear through late winter and spring on growth made the previous year, so trim after flowering rather than before.