Plant Guide

Cordyline australis

ti-kouka, cabbage tree

Tall, evergreen tree, endemic to New Zealand, with a rounded canopy consisting of large clusters of long, narrow leaves. Common throughout New Zealand in open ground, around swamps and damp places, and along forest margins. The leaves are linear with an entire margin, and up to 1 m long by 6 cm wide. They turn brown with age and remain hanging on the tree for a long time before falling, forming a skirt beneath the young green leaves. Large panicles of small, 0.5 cm wide, creamy white, strongly scented flowers are produced on mature trees in summer, attracting bees. Birds like the blue-white berries that are formed subsequently. Cordyline australis grows to about 15 m high, with an unbranched trunk when young (and undamaged), and forming side-branches in the upper part later.

The Maoris used the leaves of Cordyline australis for medicinal purposes, and the roots of young trees as a source of food. Early settlers hollowed out the trunks of large specimens to make chimneys, since the timber (unlike the foliage) is fire-resistant. They used to boil and eat young shoots as a substitute for cabbage, hence the common name. 

Prefers a position in full sun or partial shade. Likes moist soil, but can cope with considerable drought once established. Grows in just about any soil type, including clay soils as long as they are not too impermeable. Tolerates moderate frosts (to zone 8) and is hardy throughout New Zealand. Suitable for coastal and exposed sites. Caterpillars may cause some leaf damage. Stressed trees are susceptible to rust. In warm, humid areas root rot (Phytophtora) may become a problem, but can be avoided by growing other plants beneath the trees to keep their root-zones cool.

Great choice for a stunning architectural statement. Imagine a group of cabbage trees with a simple, contrasting under-planting of Muehlenbeckia astonii. You may want to plant Cordyline australis at some distance from your lawn....the lawnmower doesn't like the tough old leaves! Useful as a primary coloniser and good for erosion control on steep banks and along streambanks.

Type of plant

Tree - Evergreen

Size

5-15 m tall

Landscape Use

architectural, fragrant flowers, coastal gardens, exposed sites, erosion control

Specifications

  • Temperature: Half hardy
  • Light: Medium High
  • Moisture: Low Medium High
  • Soil: Light Medium Heavy
  • Wind tolerance: High
  • Coastal tolerance: High