Daisy Bush
Olearia allomii
shrubs -description">Endemic to Rēkohu/Wharekauri (Chatham Islands). Coastal shrub/small tree tolerant of wind and salt. Provide full sun, very free‑draining soils and light formative pruning.
Description
Olearia allomii is a leathery‑leaved Chatham Islands tree daisy with stiff, glossy upper leaf surfaces and densely tomentose undersides, bearing clusters of daisy heads with white rays and yellowish discs. Habit is a compact, wind‑firm shrub to small tree on exposed coastal sites, developing a sturdy framework that clothes to the base in high light.
Quick Facts
Coastal, oceanic climates with even rainfall and cool summers. Performs best in full sun with rapid drainage and constant air movement. Tolerates wind and salt spray but resents heavy, waterlogged soils; shelter lightly in the most extreme onshore winds when young.
| Scientific Name | Olearia allomii |
|---|---|
| Height | 2-8 m (varies with site) |
| Spread | 40-120 cm across |
| Water Needs | Low to moderate; free-draining soils |
| Light | Full sun |
| Frost Tolerance | High - tolerant of severe freezes |
| Salt Tolerance | Moderate to high (coastal species) |
| Growth Rate | Slow to moderate |
| Lifespan | Long-lived perennial |
Climate Suitability
Coastal, oceanic climates with even rainfall and cool summers. Performs best in full sun with rapid drainage and constant air movement. Tolerates wind and salt spray but resents heavy, waterlogged soils; shelter lightly in the most extreme onshore winds when young.
| City | Climate Suitability |
|---|---|
| WhangÄrei | Suitable |
| Whangārei | Ideal |
| Auckland | Suitable |
| Hamilton | Suitable |
| Tauranga | Suitable |
| Rotorua | Suitable |
| Gisborne | Suitable |
| New Plymouth | Suitable |
| Napier | Suitable |
| Whanganui | Suitable |
| Palmerston North | Suitable |
| Wellington | Suitable |
| Nelson | Suitable |
| Christchurch | Suitable |
| Dunedin | Suitable |
| Invercargill | Suitable |
Habitat
Natural Distribution
Coastal shrublands and forest edges on the Chatham Islands, typically on free‑draining sandy or rocky substrates exposed to persistent wind and salt. Occurs on bluffs, dunes and open margins where competition is limited and light is abundant.
Conservation Status
Current Threats and Protection
Assessed as At Risk – Naturally Uncommon. Localised pressures include browsing, weed invasion and loss of open coastal habitat. Retaining wind‑shorn shrublands, excluding stock and managing weeds support ongoing recruitment.
How to Grow
Cultivation Requirements
In full sun with rapid drainage. Water during extended dry spells in establishment. Tolerates salt‑laden winds; lightly shelter in the harshest exposures when young.
Planting Guide
Best Planting Practices
Plant Olearia allomii in spring or autumn in a sunny, exposed position with very free-draining soil, mimicking its natural coastal habitat. Ensure good air circulation and shelter young plants from the harshest winds during establishment. Light formative pruning after flowering helps maintain its compact, wind-firm shape and promotes dense growth.
Ecological Role
Environmental Benefits
Flowers provide nectar and pollen for invertebrates; the dense, wind‑tolerant canopy offers shelter on exposed coasts. As part of coastal shrubland mosaics it helps bind fragile substrates and protect interiors from salt‑laden winds.
Uses
Traditional and Modern Applications
A hardy coastal shrub for windy sites, dune stabilisation and exposed gardens. Use as a clipped screen or allow a natural, wind‑pruned form in coastal plantings; pairs well with sedges and other Chatham taxa.
Landscaping Uses
Garden Design Applications
Mass along seaward edges to create a tough, salt‑tolerant buffer. Combine with divaricate shrubs and tussock grasses for texture, using gravel or shell mulches to reinforce the maritime character.
Seasonal Care
Year-Round Maintenance
Spring management focuses on removing winter-damaged foliage and assessing drainage. Summer care emphasizes maintaining adequate moisture without waterlogging. Autumn preparation includes reducing irrigation and ensuring good air circulation. Winter protection may require covering in areas subject to excessive moisture. Year-round monitoring ensures early detection of problems and maintenance of optimal growing conditions.
Pruning
Pruning Techniques
Responds well to regular light trimming to maintain density and a tidy outline. After flowering, tip‑prune to encourage branching and remove any storm‑damaged shoots. Avoid hard cuts into old wood, which can be slow to reshoot in exposed sites.
How to Grow Daisy Bush
From Seed
Propagation of Olearia allomii from fresh seed is a viable method. Collect seeds (achenes) from the dried flower heads in late summer to autumn. Sow the seeds onto a very free-draining, gritty seed-raising mix, lightly covering them. Olearia seeds often benefit from a period of cold stratification (e.g., 4-8 weeks in a refrigerator) to break dormancy, mimicking natural winter conditions. Maintain cool, airy conditions and consistent moisture (avoiding waterlogging) in a protected environment. Germination can be erratic and slow, often taking several weeks to months. Once seedlings are robust enough to handle, prick them out into individual pots and grow them on in a cool, bright, and well-ventilated location until strong enough for planting out.
From Cuttings
Olearia allomii can be successfully propagated from semi-hardwood cuttings taken in late summer or early autumn. Select healthy, firm stem segments, about 10-15 cm long, from the current season's growth. Remove the lower leaves and dip the cut end in a rooting hormone to encourage root development. Insert the cuttings into a free-draining rooting medium such as a mix of sand and perlite. Maintain high humidity around the cuttings, either by placing them in a propagation chamber or covering them with a plastic bag, and ensure consistent moisture in the rooting medium. Keep in a warm, bright location out of direct sunlight. Rooting typically occurs within 8-16 weeks. Once rooted, gradually acclimatize plants to ambient conditions before potting up.
General Cultivation
Allom's Tree Daisy is a tough, wind-firm shrub to small tree, endemic to the Chatham Islands, that thrives in full sun and very free-draining soils. It is particularly well-suited for coastal and exposed sites due to its high tolerance to wind and salt spray. Plant in a lean, gritty, mineral substrate (e.g., a high proportion of sand or fine gravel) with excellent drainage and constant air movement. It resents heavy, waterlogged soils, which can lead to root rot. Provide full sun in cool climates, and protect with light shelter from the harshest onshore winds when young. Water needs are low to moderate once established; it is highly drought-tolerant but benefits from occasional watering during prolonged dry spells. Minimal pruning is required; light formative pruning can encourage a compact, bushy habit and a tidy outline. Remove any dead or storm-damaged shoots after flowering.
Pests and Diseases
Common Problems and Solutions
Generally robust in coastal air. Heavy, stagnant soils can cause root stress-improve drainage and avoid burying crowns. Thin lightly to improve airflow if scale or sooty mould develops in sheltered corners.
Cultural Significance
Traditional Uses and Values
A distinctive member of the Chatham Islands coastal flora. Planting eco‑sourced stock in restoration supports local whakapapa and helps maintain the character of wind‑shorn shrublands that protect the islands’ shores.
Bonus Tip
Expert Growing Advice
To truly showcase the distinctive Chatham Island character of Olearia allomii, allow it to develop its natural wind-pruned form in a sunny, exposed coastal position with very free-draining soil. Its tough, glossy leaves and prolific daisy flowers are best appreciated when the plant is grown in conditions that mimic its wild, windswept habitat.
