Pittosporum crassifolium native plants index
Karo (scientific name: Pittosporum crassifolium) Karo is a hardy coastal native tree renowned for its thick, leathery grey‑green leaves and remarkable tolerance of salt spray and wind. With fragrant crimson to purple flowers in spring and fast growth, it's an exceptional choice for coastal gardens and shelter plantings. Explore more in the native plants index.
| Scientific Name | Pittosporum crassifolium |
|---|---|
| Height | 3-10 m |
| Spread | 2-6 m |
| Water Needs | Low to moderate |
| Light | Full sun to partial shade |
| Frost Tolerance | Moderate when mature |
| Salt Tolerance | Excellent |
| Growth Rate | Fast |
| Lifespan | Long-lived |
Regional climate suitability across major New Zealand cities.
| City | Climate Suitability |
|---|---|
| Whangārei | Ideal |
| Auckland | Ideal |
| Hamilton | Ideal |
| Tauranga | Ideal |
| Rotorua | Ideal |
| Gisborne | Ideal |
| New Plymouth | Ideal |
| Napier | Ideal |
| Whanganui | Ideal |
| Palmerston North | Ideal |
| Wellington | Ideal |
| Nelson | Ideal |
| Christchurch | Ideal |
| Dunedin | Ideal |
| Invercargill | Ideal |
Karo prefers dry, free‑draining soils and is remarkably adaptable to poor coastal conditions. It naturally grows on steep slopes, cliff faces, and boulder beaches, making it excellent for challenging sites where other plants struggle.
Karo adapts to both full sun and partial shade, with growth habit varying by exposure. In full sun it maintains a compact 3m height, while in shade it stretches to reach light and can grow up to 6m tall.
Karo has low to moderate water needs and is drought‑tolerant once established. Regular watering during establishment helps develop strong roots, but mature plants can withstand dry periods.
Karo provides important habitat and food sources for native and introduced birds. The fragrant spring flowers attract pollinators, while the seeds are widely distributed by birds, often appearing spontaneously in gardens. The dense foliage offers excellent nesting sites.
The name "crassifolium" means "thick leaf" in Latin, referring to its distinctive leathery foliage. Karo has been an important coastal species for both Māori and European settlers, valued for its hardy nature and ability to provide shelter in harsh coastal conditions.
Karo is exceptional for coastal gardens, shelter belts, and challenging sites. Its fast growth, salt tolerance, and attractive appearance make it ideal for hedging, screening, and structural plantings in both formal and informal landscapes.
Spring is the optimal planting season for Karo and brings the spectacular flowering period (August‑October) with richly scented crimson to purple flowers. This is also the time for annual pruning and establishment care.
Summer requires attention to watering for newly planted trees, though established plants are very drought‑tolerant. This is when the green seed capsules begin to develop from the spring flowers.
Autumn is another excellent planting season and the time for final pruning. Seed capsules ripen and split open to reveal black seeds, with the orange‑colored capsule interiors adding ornamental interest.
Winter is the rest period for Karo, though established plants are frost‑tolerant. Young plants may need protection from severe frosts, but mature trees handle moderate frosts and even snowfall well.
Karo responds excellently to pruning and benefits from annual trimming to maintain optimal health and appearance. Regular pruning promotes dense growth and prevents the plant from becoming leggy, especially important for hedging applications.
Karo is a hardy coastal native tree renowned for its thick, leathery grey-green leaves and remarkable tolerance of salt spray and wind. With fragrant crimson to purple flowers in spring and fast growth, it's an exceptional choice for coastal gardens and shelter plantings. Understanding its propagation methods is key to successfully growing this delightful species.
Propagating Karo from fresh seed is a very easy and effective method, often resulting in spontaneous seedlings appearing in gardens as birds distribute the seeds widely. The ripe capsules split open in autumn to reveal black seeds ready for collection. Collect seeds when capsules split open (September-autumn). Remove seeds from orange-lined capsules. Sow fresh seeds immediately in a well-draining seed-raising mix. Keep soil consistently moist and provide bright light. Germination is typically reliable and fairly quick. Transplant seedlings when large enough to handle. Watch for natural seedlings appearing around mature plants.
Semi-hardwood cuttings taken in late summer to early autumn provide a reliable method to propagate known characteristics and maintain specific growth forms. Take 10-15cm cuttings from current season's growth. Select semi-hardwood material in late summer/early autumn. Remove lower leaves, keeping top leaves. Dip in rooting hormone for better success rates. Plant in well-draining propagation mix. Provide a humid environment and bright, indirect light. Roots typically develop within 6-10 weeks. Transplant when a well-rooted system is established.
Plants with similar habit or use can complement Karo in mixed native plantings and habitat restoration.
Karo (Pittosporum crassifolium) has cultural and ecological significance in Aotearoa New Zealand. It supports native biodiversity, contributes to habitat structure, and is valued in restoration and garden plantings. Within mātauranga Māori, native plants like this help sustain the health of the ngahere (forest) and local ecosystems.
