Kawakawa
Piper excelsum
This native plant, known as Kawakawa(scientific name: Piper excelsum ), is a remarkable species endemic to New Zealand. It is characterized by its unique features, ecological role, and cultural significance. This comprehensive guide provides detailed information on its care, propagation, and importance within the New Zealand ecosystem. Understanding this plant contributes to the appreciation of our rich biodiversity and heritage, and supports conservation efforts for Browse All .
Plant Description
Identification and Physical Characteristics
Kawakawa ( Piper excelsum ), also known as New Zealand peppertree, is a small tree or densely branched shrub belonging to the pepper family (Piperaceae) Discover more about native grasses. It typically grows up to 6 meters tall, or a densely branched shrub. The leaves are a distinctive feature, being large (5-10 cm long by 6-12 cm wide), heart-shaped, broadly rounded with a short tip, and often glossy. They are deep green in forest environments but can be yellowish-green in more open areas. A common characteristic is the presence of holes in the leaves, caused by the kawakawa looper moth caterpillar. The stems are fleshy, green, and have noticeable swollen or knobbly joints (nodes), giving the plant a unique "jointed" appearance. Minute flowers are produced on greenish, erect spikes, typically 2.5-7.5 cm long. Male and female flowers are often found on separate plants. After pollination, the flowers develop into small, berry-like fruits that are yellow to bright orange. These fruits are edible and serve as a food source for birds.
Quick Facts
| Scientific Name | Piper excelsum |
|---|---|
| Height | 2-6 m |
| Spread | 2-5 m |
| Water Needs | Moderate, drought tolerant when established |
| Light | Dappled light to partial shade |
| Frost Tolerance | Frost tender |
| Salt Tolerance | Moderate |
| Growth Rate | Fast |
| Lifespan | Long |
Climate Best Suited to
Piper excelsum is well adapted to various New Zealand regions.
Regional Suitability
| City | Climate Suitability |
|---|---|
| Auckland | High |
| Wellington | High |
| Christchurch | Medium |
Plant Habitat
Natural Occurrence and Ecology
Kawakawa ( Piper excelsum ) is a small tree or densely branched shrub endemic to New Zealand, found throughout the North Island, the northern parts of the South Island, and on the Chatham Islands. It thrives in coastal to lowland forests, typically at elevations up to 500 meters above sea level.Sheltered and Moist:Kawakawa prefers sheltered locations with consistent moisture and protection from harsh winds and extreme temperatures. It is often found in the understory of forests, along stream banks, and in damp gullies.Soil:It thrives in free-draining but consistently moist soils, rich in organic matter. While adaptable to various soil types, it performs best in well-structured, fertile soils.Light:As an understory species, it is exceptionally shade tolerant and prefers dappled light conditions. While it can survive in full sun, it performs best with protection from intense afternoon sunlight.Widespread:Its natural distribution extends from Te Paki in the far north to North Canterbury and Banks Peninsula in the south, showcasing its adaptability across a significant portion of New Zealand.Coastal to Lowland:It is a common sight in coastal forests, particularly in areas with high humidity and mild temperatures.As a cold-sensitive species, kawakawa cannot tolerate frost and prefers the warmer, more humid conditions found in its natural range. Its presence is a key indicator of healthy, undisturbed native forest ecosystems.
Growing Requirements
Soil Requirements
Prefers well-draining soil rich in organic matter.
- Well-drained
- Loamy
Light Requirements
Grows best in partial to full sun.
- Full Sun
- Partial Shade
Water Requirements
Requires regular watering during dry periods.
- Regular
- Drought tolerant once established
Planting and Establishing
Establishment Guidance
Plant Piper excelsum in a hole twice the width of the root ball.
Proper establishment is key to long-term success. Ensure the planting hole is twice as wide as the root ball and backfill with a mix of native soil and organic compost. Initial watering should be thorough, followed by regular monitoring during the first two growing seasons to ensure the plant becomes well-anchored and resilient to local climate fluctuations.
Ecological Role
Biodiversity and Ecosystem Impact
Provides habitat and food for native fauna.
This species plays a vital role in its local ecosystem, providing essential habitat and food sources for native biodiversity. Its presence supports complex ecological interactions, contributing to the overall health and stability of the environment. By planting this native, you help maintain the intricate web of life that defines New Zealand's unique natural heritage.
Uses & Significance
Garden Uses
Ideal for rock gardens and native borders.
- Rock gardens
- Ground cover
Ecological Value
Supports local pollinators.
- Birds
- Insects
The versatility of this plant makes it a valuable addition to many New Zealand gardens. Beyond its aesthetic appeal, it offers practical benefits such as soil stabilization and shelter for smaller plants. Its historical and modern uses highlight its enduring importance in both traditional practices and contemporary landscape design, making it a thoughtful choice for any restoration or gardening project.
Landscaping Uses
Adds texture and form to modern landscapes.
In a landscape setting, this plant provides excellent structure and year-round interest. Its unique form and foliage can be used to create focal points or as a cohesive element in a larger native planting scheme. It pairs well with other New Zealand natives, allowing for the creation of diverse and resilient garden environments that reflect the natural beauty of Aotearoa.
Seasonal Care Calendar
Spring
Mulch and apply balanced fertilizer.
- Fertilize
- Mulch
Summer
Water deeply during dry spells.
- Water
- Check for pests
Autumn
Tidy up any dead foliage.
- Prune lightly
- Plant new specimens
Winter
Protect from heavy frosts if necessary.
- Frost protection
When to Prune and How Much
Minimal pruning required to maintain shape.
- Remove dead branches
Always use clean, sharp tools.
Regular maintenance through careful pruning ensures the plant remains healthy and maintains its desired shape. Focus on removing dead or diseased wood to promote better air circulation and prevent the spread of pathogens. Proper pruning techniques help the plant direct its energy toward new growth, resulting in a more robust and aesthetically pleasing specimen in your garden.
How to Grow Kawakawa
Cultivating Piper excelsum ( Piper excelsum ) is a rewarding endeavor for any gardener interested in New Zealand's unique flora. This species can be propagated through several methods, each requiring specific conditions to ensure healthy growth and establishment. Successful propagation depends on mimicking the plant's natural environment and providing consistent care during the early stages of development.
From Seed
Propagation from seed is often the most effective way to produce a large number of Piper Excelsum plants. Seeds should be collected when they are fully mature. Freshly collected seeds generally have higher germination rates than those that have been stored for long periods.
Sow fresh seeds in a seed-raising mix.
- Collect seeds
- Sow in trays
Keep moist until germination.
From Cuttings
For those wishing to replicate specific characteristics of a parent plant, vegetative propagation via cuttings is the preferred method. This technique ensures that the new plants are genetically identical to the source. Semi-hardwood cuttings taken during the appropriate season usually yield the best results for this species.
Take semi-hardwood cuttings in late summer.
- Take cuttings
- Use rooting hormone
Additional Methods
Depending on the growth habit of Piper excelsum , other methods such as division or layering might also be viable options. Division is particularly suitable for plants that form dense clumps or have spreading root systems, while layering can be used for species with trailing or flexible stems.
Division can be done in early spring.
- Divide clumps
- Replant immediately
Pests & Diseases
Generally resistant to major pests.
While generally resilient, maintaining optimal growing conditions is the best defense against pests and diseases. Regular monitoring allows for early detection of any issues, which can often be managed through cultural practices or organic interventions. Ensuring good air circulation and appropriate watering will significantly reduce the plant's susceptibility to common environmental stresses and pathogens.
Cultural Significance
Kawakawa ( Piper excelsum ) holds profound spiritual and cultural importance for Māori as a taonga (treasure) species. It plays central roles in welcoming ceremonies, with hosts waving kawakawa leaves to greet visitors at marae. The plant is associated with life transitions, used in naming ceremonies, to remove tapu (spiritual restrictions), and worn as wreaths during tangi (funerals) as a symbol of mourning and respect.Medicinal Use (Rongoā Rākau):Kawakawa is one of the most important traditional Māori medicinal plants (rongoā rākau). It is used to treat a wide array of ailments, including digestive and urinary issues, skin complaints, dental pain (due to its numbing properties), colds, and kidney problems. Leaves with natural holes are often preferred for medicinal purposes, as they are believed to be more potent.Ceremonial and Ritual Context:The plant is utilized in ceremonies and rituals. The Māori word "kawa" means both "bitter" and "protocol," highlighting its role in cultural protocols (tikanga). It is also traditionally used as a symbol of mourning.Symbolism:Kawakawa is seen as a symbol of death, often contrasted with rangiora (Brachyglottis repanda), which symbolizes life.Relationship to Kava: Piper excelsum is a relative of kava (Piper methysticum), a psychoactive beverage plant from the Pacific Islands. The Māori name "kawakawa" is derived from "kavakava," suggesting early Polynesian settlers recognized its resemblance to kava. However, Piper excelsum itself does not possess psychoactive properties.Other Uses:The aromatic fruit and leaves have been used. The ripe fruit is edible, and its seeds can be used as a culinary spice. The leaves can also flavor drinks like tea or beer, though caution is advised regarding consumption quantity due to potential toxicity. Historically, smoke from burning leaves was used as an insecticide.Modern Appreciation:Kawakawa continues to be valued today, appearing in waiata (songs) and carving motifs. Its distinctive peppery scent is appreciated, and it is incorporated into botanical skincare products, with traditional harvesting practices often maintained to respect cultural protocols and the environment.
- Traditional medicine
- Crafts
Bonus Tip
Excellent for low-maintenance gardens.
For an extra boost, consider applying a thin layer of high-quality organic mulch around the base of the plant. This helps retain soil moisture, suppresses weeds, and gradually improves soil structure as it breaks down. This simple step can make a significant difference in the plant's overall vigor and resilience, especially during periods of extreme weather.
Related Plants
Explore other native plants that share similar characteristics or habitats with Piper excelsum ( Piper excelsum ), offering further insights into New Zealand's diverse flora. These related species provide context and opportunities for complementary planting in your garden.
Plant Conservation
Conservation Status
Piper excelsum , commonly known as kawakawa, has a conservation status of "Not Threatened." This species, including its subspecies Piper excelsum subsp. excelsum, is endemic to New Zealand. It is found throughout the North Island and extends to the South Island, growing in coastal areas and lowland forests.