Sand Coprosma
Coprosma acerosa
Sand Coprosma is a low-growing, sprawling shrub native to New Zealand's coastal areas. Its distinctive wire-like branches and translucent blue berries make it an attractive and hardy addition to seaside gardens. The plant plays an important role in dune stabilization and provides food for native birds.
Sand Coprosma (Coprosma acerosa) with its characteristic wire-like branches and blue berries. Image by Phil Bendle [CC BY-NC-ND 3.0], via Wikipedia
Quick Facts
| Scientific Name | Coprosma acerosa |
|---|---|
| Height | 0.3–1 m (1–3 ft) tall, usually prostrate or low-growing |
| Spread | 1–3 m (3–10 ft) wide, often spreading along the ground |
| Water Needs | Low; drought-tolerant once established |
| Light | Full sun to partial shade (best in full sun) |
| Frost Tolerance | Moderate (tolerates light frosts, protect from severe frost) |
| Salt Tolerance | Very high (excellent tolerance for coastal salt and wind) |
| Growth Rate | Moderate (faster in ideal coastal conditions) |
| Lifespan | Long-lived (decades in suitable conditions) |
Climate Suitability
Distribution Map
Sand Coprosma is found along New Zealand's coasts, especially on sandy dunes and exposed beaches from Northland to Southland. It is a key species for coastal restoration and dune stabilization.
| City | Suitability |
|---|---|
| Whangārei | Suitable |
| Auckland | Suitable |
| Hamilton | Marginal (prefers coast) |
| Tauranga | Suitable |
| Rotorua | Marginal (prefers coast) |
| Gisborne | Suitable |
| New Plymouth | Suitable |
| Napier | Suitable |
| Whanganui | Marginal (prefers coast) |
| Palmerston North | Marginal (prefers coast) |
| Wellington | Suitable |
| Nelson | Suitable |
| Christchurch | Suitable |
| Dunedin | Marginal (prefers coast) |
| Invercargill | Marginal (prefers coast) |
Coprosma acerosa (sand coprosma) is best suited to coastal areas but can tolerate some inland conditions.
Growing Requirements
Soil
- Well-draining sandy soil
- Tolerates poor soils
- pH 5.5-7.5
Light
- Full sun to partial shade
- Best growth in full sun
- Tolerates coastal exposure
Water
- Low water needs
- Drought tolerant
- Avoid waterlogging
Uses & Significance
Garden Uses
- Coastal gardens
- Ground cover
- Rock gardens
- Erosion control
- Native bird gardens
- Used by Māori for stabilizing sand dunes and protecting coastal ecosystems. Its presence is a sign of healthy dune systems.
- Dune stabilization
- Bird food source
- Coastal habitat
Seasonal Care
Spring
Check for new growth and lightly trim to shape if needed. Mulch to retain moisture and suppress weeds.
Summer
Water young plants during prolonged dry spells. Established plants are drought tolerant.
Autumn
Remove any dead or damaged branches. Monitor for signs of stress after storms.
Winter
Minimal care required. Ensure good drainage to prevent root rot.
Pruning
Prune Coprosma acerosa in late winter or early spring to maintain its shape and encourage bushiness. Remove any dead, damaged, or tangled stems. Avoid heavy pruning, as the plant’s natural form is part of its appeal.
Planting Guide
- Choose a sunny, well-drained site, ideally with sandy or light soil.
- Dig a hole twice the width of the root ball.
- Place the plant at the same depth as in the pot, backfill, and firm gently.
- Water well after planting. Mulch to conserve moisture and suppress weeds.
- Space plants 1–2 meters apart for ground cover or dune stabilization.
Propagation
Coprosma acerosa can be propagated from semi-hardwood cuttings taken in late summer or autumn. Dip cut ends in rooting hormone and place in a free-draining mix. Keep moist and sheltered until roots develop. It can also be grown from fresh seed, though germination may be slow and variable.
Cultural History
Coprosma acerosa is valued in Māori tradition for its role in stabilizing sand dunes and protecting coastal ecosystems. Its berries are eaten by native birds, and the plant is an important part of natural coastal restoration projects in New Zealand.
Pests & Diseases
- Generally pest and disease free.
- Occasionally susceptible to scale insects or root rot in poorly drained soils.
- Monitor for signs of stress, especially in wet conditions.
Bonus Fact
Coprosma acerosa’s blue berries are not only attractive but also provide a valuable food source for native birds such as the tūī and kererū. Its dense, wiry growth makes it excellent for erosion control and habitat creation in coastal gardens.
