Taupata
Coprosma petiolata
Coprosma petiolata, commonly known as taupata, is an endemic vascular shrub or small tree native to the Kermadec Islands, specifically Raoul Island and its adjacent Herald Islets. This evergreen plant typically presents as a prostrate, spreading, or erect shrub, or a widely spreading tree that can reach up to 6 meters in height, though it is usually smaller. native shrubs
Plant Description
Its branches have rough, dark to light grey bark, and its branchlets are slender and pubescent (hairy). The leaves are a key feature: they are arranged in pairs, are green and very glossy, and have a leathery texture. They range from 10-70 mm long, are widest towards their blunt tip, and have distinct reticulated veins visible on the underside. In exposed conditions, the leaves may be light yellow-green with a waxy bloom, while in shaded areas, they are greener. Small, triangular, dark-tipped flaps are present on the stem between leaf pairs. Male flowers are clustered on slender peduncles, while female flowers usually appear in groups of three on slender, pubescent peduncles. The plant produces orange-red, ovoid or subdidymous drupes (fleshy fruits) that are 6-10 mm in size.
Quick Facts
| Scientific Name | Coprosma petiolata |
|---|---|
| Height | Up to 6m |
| Spread | Up to 3m |
| Water Needs | Moderate |
| Light | Full sun to partial shade |
| Frost Tolerance | Frost-tender |
| Salt Tolerance | High |
| Growth Rate | Moderate |
| Lifespan | Long |
Climate Best Suited to
Coprosma petiolata thrives in coastal environments. It is commonly found on rock stacks, islets, coastal cliffs, and associated talus slopes and boulder fields. It often forms a dominant component of coastal scrub and can be found as an understorey shrub in more exposed dry forests of the Kermadec Islands. It is also locally common on the exposed slopes of the Raoul Island crater walls.
Regional Suitability
| 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 | Moderate |
| Dunedin | Moderate |
| Invercargill | Moderate |
Plant Habitat
Coprosma petiolata thrives in coastal environments. It is commonly found on rock stacks, islets, coastal cliffs, and associated talus slopes and boulder fields. It often forms a dominant component of coastal scrub and can be found as an understorey shrub in more exposed dry forests of the Kermadec Islands. It is also locally common on the exposed slopes of the Raoul Island crater walls.
Plant Conservation
Coprosma petiolata is classified as an abundant endemic species. It is listed primarily because it is endemic to the Kermadec Islands. On Raoul Island, it occasionally hybridizes with Coprosma acutifolia.
Growing Requirements
Soil Requirements
It thrives in well-draining soil. When planting in the ground, incorporating compost and sheep pellets can improve soil quality. For container planting, a container mix with moisture retention properties is recommended.
- Prefers well-draining soil
Light Requirements
Coprosma petiolata prefers partial to full sunlight.
- Full sun to partial shade
Water Requirements
While drought-tolerant, it benefits from regular watering, especially during its first year to establish roots. The soil should be allowed to nearly dry out between waterings, typically every 2-3 weeks. Occasional misting can help replicate humidity.
- Water every 2-3 weeks
- Drought tolerant
Planting Guide
The best time to transplant Coprosma petiolata is from early spring through late spring, allowing the plant to establish roots before summer heat. The new location should offer partial to full sunlight and well-draining soil, avoiding overly windy spots.
Ecological Role
The orange-red drupes of Coprosma petiolata serve as an important food source for native birds, including bellbirds, tūī, and various smaller passerine species. This endemic coprosma plays a vital role in New Zealand's forest ecosystems, contributing to the understory structure and providing shelter for numerous wildlife species. The plant's flowers attract native pollinators such as flies and small beetles, supporting the intricate web of ecological relationships within native forests. Its ability to tolerate partial shade makes it an important component of forest regeneration, often establishing beneath taller canopy trees and helping to create suitable conditions for other native species to establish.
Uses & Significance
Garden Uses
This species is considered an attractive and hardy shrub suitable for coastal situations.
- Coastal gardens
- Specimen shrub
The genus name "Coprosma" comes from the Greek words for "dung" and "smell," referring to the genus's foul odor.
- Genus name refers to foul odor
Ecological Value
The fruit of Coprosma petiolata is a food source for native birds.
- Food source for native birds
Landscaping Uses
In a landscaping context, Coprosma petiolata is an excellent choice for a coastal garden. It can be used as a hedge or as a specimen shrub. Its tolerance of salt spray makes it a very useful plant for seaside locations.
Seasonal Care Calendar
Spring
In spring, new growth will appear. This is a good time to lightly prune the plant to maintain its shape.
- Lightly prune to shape
Summer
During summer, regular watering is beneficial, especially during dry spells.
- Water regularly
Autumn
In autumn, the fruit will ripen. This is a good time to collect seed for propagation.
- Collect seed
Winter
In winter, the plant is largely dormant. Pruning is generally not required.
- Minimal care required
When to Prune and How Much
Pruning should be done in early spring before new growth begins to encourage a dense, healthy structure. This involves removing dead or diseased branches and trimming excessive growth to shape the plant and improve air circulation. Avoid heavy pruning in late summer to prevent winter damage.
- Prune in early spring
Always use clean, sharp tools for pruning to minimize the risk of disease.
How to Grow Taupata
From Seed
Coprosma petiolata can be successfully propagated from fresh seeds, offering excellent results when proper collection and processing techniques are employed. The species produces small, colorful berries that ripen during autumn months, typically between March and May. Fresh seeds have significantly higher viability rates than stored seeds, making immediate processing essential for optimal germination success. Seeds require removal from the fleshy fruit and benefit from brief stratification periods to break dormancy mechanisms.
Collect ripe berries when they have developed full coloration but remain firm to the touch. The flesh should be completely removed by gently mashing berries in water, then floating away the pulp to leave clean seeds. Rinse seeds thoroughly and surface sterilize with diluted fungicide solution to prevent fungal diseases during germination. Sow immediately in a well-draining seed-raising mix containing equal parts quality potting mix, coarse sand, and perlite to ensure adequate drainage and aeration.
Maintain consistent soil moisture without waterlogging, keeping temperatures between 15-20°C for optimal germination conditions. Provide bright, indirect light and ensure good air circulation to prevent damping-off diseases. Germination typically occurs within 6-12 weeks but can occasionally extend to several months, requiring patience from propagators. Once seedlings have developed their second pair of true leaves, transplant carefully to individual containers using a moisture-retentive but well-draining native plant potting mix.
From Cuttings
Coprosma petiolata responds very well to vegetative propagation from semi-hardwood cuttings, offering faster results than seed propagation while maintaining parent plant characteristics. Semi-hardwood cuttings taken during summer or early autumn show the highest success rates when new growth has begun to mature but retains some flexibility. This timing coincides with optimal hormone levels in the plant tissue, enhancing rooting potential.
Select healthy, disease-free shoots from the current season's growth, avoiding any flowering branches which typically have lower rooting success. Take cuttings approximately 10-15cm long, making clean cuts with sharp, sterile secateurs just below a leaf node. Remove all leaves from the bottom third of the cutting and trim remaining leaves by half to reduce transpiration losses during the rooting process. The petioles (leaf stalks) should be retained as they contain natural rooting hormones that aid establishment.
Dip the base of each cutting in rooting hormone powder or gel containing IBA (indole-3-butyric acid) at 3000-4000ppm concentration to enhance root development. Plant cuttings in a well-drained cutting mix composed of equal parts coarse sand, perlite, and peat moss or coconut coir. Insert cuttings to approximately one-third their length, ensuring good contact between cutting and growing medium. Maintain consistent moisture levels and high humidity (75-85%) using misting systems or clear plastic covers. Provide bottom heat to maintain soil temperature around 20-25°C, along with bright, filtered light to promote healthy growth without scorching developing roots.
Pests & Diseases
Coprosma petiolata is generally a robust, pest and disease-free plant, making it an excellent choice for low-maintenance native gardens. In cultivation, the most common issues are related to environmental stress rather than pest attacks. Poor drainage can lead to root rot, while prolonged dry conditions may cause leaf drop. Occasionally, scale insects may affect plants grown in very sheltered conditions with poor air circulation. Browsing by possums can be a problem in some areas, particularly when young shoots are tender. Regular monitoring and maintaining good growing conditions typically prevent any serious health issues in this hardy native shrub.
Cultural Significance
Coprosma species are significant elements of native shrublands and forests in Aotearoa. While specific traditional uses for Coprosma petiolata are not widely documented, some members of the genus have had berries eaten when ripe, and the plants play an ongoing role in restoration and mahinga kai for birds.
- Important genus in native shrubland/forest communities
- Some Coprosma species"™ berries were eaten when ripe
- No species-specific records widely available for this taxon
Bonus Tip
The name "petiolata" refers to the plant's stalked leaves, a distinguishing feature that sets it apart from many other coprosma species which have sessile (stalkless) leaves attached directly to the stem. The petioles (leaf stalks) are typically 5-15mm long and often have a reddish tinge, particularly in younger growth. This characteristic, combined with the plant's preference for shaded forest understory conditions, makes identification easier in the field. When propagating from cuttings, include a portion of the petiole as this contains growth hormones that improve rooting success rates.
Related Plants
Explore other native shrubs that share similar characteristics or habitats with Coprosma petiolata, offering further insights into New Zealand's diverse flora.