Vegetable Sheep
Raoulia eximia native plants index
Introduction
Vegetable Sheep (scientific name: Raoulia eximia) is one of New Zealand's most distinctive alpine plants, forming enormous woolly cushions that from a distance can resemble sleeping sheep. This remarkable cushion plant grows slowly in the harsh alpine environments of the South Island, creating dense mats covered in silvery woolly leaves. It's an iconic symbol of New Zealand's unique high-country flora. Explore more in the native plants index.
Plant Description
Botanical Features
Vegetable Sheep (Raoulia eximia), also known by its Mori name tuthuna, is a species of plant in the Asteraceae family, endemic to New Zealand. It is notable for its dense, hard, and convex cushion-like form, which from a distance resembles a sheep. These cushions can grow quite large, up to 2 meters across and 1 meter thick or tall. The unique shape is formed by its very stiff, densely compacted, and highly branched woody stems. The plant's small, woolly leaves, about 1/8 inch long, are tightly packed at the ends of its twigs and are often completely hidden by soft, white, velvety hairs. Only the tiny buds, which never fully unfold, are typically visible externally. The rosettes of leaves are tightly packed, sometimes forming geometric designs of hexagons and pentagons, covered with silky, silvery hairs. The youngest leaves in the center of each rosette are less hairy, giving a darker grey-green "eye" appearance. Raoulia eximia typically has a grey to grey-green coloration. Its flowerheads are small, about 3mm across, and crimson in color, with yellowish-white flowers blooming in late spring or summer.
Quick Facts
Essential Information
| Scientific Name | Raoulia eximia |
|---|---|
| Common Name | Vegetable Sheep, Tuthuna |
| Appearance | Dense, hard, convex, cushion-like masses resembling woolly sheep, up to 1 meter in diameter and height. |
| Leaves | Small, woolly, grey to grey-green leaves, tightly packed. |
| Family | Asteraceae (Daisy family) |
| Habitat | Endemic to New Zealand, found in subalpine to alpine environments (1100-1800m) in the drier mountains of the South Island. Prefers rocky ground, scree, talus slopes, cliff faces, boulder falls, and fellfields. |
| Adaptations | Dense, woolly structure protects from wind, cold, and moisture loss. Interior contains dead leaves forming spongy peat, retaining water and providing warmth. |
| Conservation Status | Not Threatened (as of 2023) |
| Propagation Difficulty | Difficult; slow-growing from seed. |
| Height | Up to 1 m diameter and height |
| Water Needs | Low; extremely drought tolerant once established |
| Light | Full sun; adapted to intense alpine conditions |
| Spread | Forming cushions up to 50 cm across |
| Frost Tolerance | Extremely hardy; alpine conditions |
| Salt Tolerance | Low; alpine species unsuited to coastal conditions |
| Growth Rate | Very slow |
| Lifespan | Long-lived alpine perennial |
Climate Best Suited to
Regional climate suitability across major New Zealand cities.
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 | Ideal |
| Dunedin | Ideal |
| Invercargill | Ideal |
Natural Habitat
Vegetable Sheep (Raoulia eximia), also known by its Mori name tuthuna, is a unique cushion plant endemic to the South Island of New Zealand. Its natural habitat is exclusively in subalpine to alpine regions, primarily found east of the main divide from Marlborough to northern Southland.
Key Habitats Include:
- Rocky Alpine Environments: This plant thrives in rocky ground, including scree and talus slopes, cliff faces, boulder falls, and fellfields. These environments are characterized by their harsh conditions.
- High Altitudes: It typically grows at elevations ranging from approximately 1,200 to 2,500 meters (3,937 to 8,202 feet) above sea level, showcasing its extreme adaptation to high-altitude, exposed conditions.
Preferred Conditions:
- Harsh Conditions: Raoulia eximia is adapted to harsh conditions, including strong winds, cold summers, frequent freeze-thaw cycles, and raw soils with low nutrient concentrations.
- Well-Drained Soils: It demands exceptionally well-draining soil, as it is highly susceptible to rot if kept wet, especially in winter.
The unique cushion-like growth and woolly foliage of the Vegetable Sheep are crucial adaptations that protect it from strong winds, cold temperatures, and intense solar radiation, while minimizing water loss. Its specialized habitat underscores its ecological importance in contributing to the biodiversity and unique flora of New Zealand's high country.
Plant Conservation
Raoulia eximia, commonly known as "vegetable sheep" or by its Māori name "tutāhuna," is endemic to New Zealand. It is primarily found in the subalpine to alpine rocky areas of the South Island, east of the main divide. As of 2023, Raoulia eximia is classified as "Not Threatened" under the New Zealand Threat Classification System (NZTCS). This assessment was updated in 2022-2023. The species is not currently listed on the IUCN Red List, suggesting a stable population within its natural range. Despite its "Not Threatened" status, Raoulia eximia faces potential threats such as habitat loss due to its restricted range and the broader impact of climate change. Propagation of the plant is considered difficult, and it is advised against removing it from the wild; it is also not commercially available. Conservation efforts for Raoulia eximia primarily focus on protecting its natural habitats, as the species is notoriously difficult to propagate. Cultivation attempts have generally proven impractical, with plants being fickle and prone to sudden collapse, even when grown from seed or hardwood cuttings. Therefore, in-situ conservation and habitat preservation are considered the most effective approaches to support this species.
Growing Requirements
Soil Requirements
Raoulia eximia demands exceptionally well-draining soil. It naturally grows in raw, low-nutrient soils, such as scree, talus slopes, and rocky outcrops. A gritty, sandy, or gravelly mix is essential to prevent waterlogging and root rot. It is adapted to soils with low concentrations of phosphorus and nitrogen.
Light Requirements
Full sun to partial shade is ideal. It thrives with bright, consistent light exposure, but in very hot climates, protection from intense midday sun can prevent scorching. Subdued lighting conditions can help mimic its natural alpine habitat.
Water Requirements
Consistent moisture is necessary, but overwatering must be strictly avoided. While it experiences high soil moisture in its natural habitat (except when frozen), it is highly susceptible to rot if kept wet, especially in winter. Good air circulation is vital. Approximately 1 inch of water per week is generally suitable, and mulching can help maintain soil moisture.
Planting Guide
Alpine Scree Conditions
Vegetable sheep (Raoulia eximia) demands sharp drainage, abundant sun, and cool air circulation. Use a deep gritty scree mix (coarse sand, pumice, and small scoria) over free-draining subsoil.
How to Establish
- Plant on a slight mound or scree slope to shed winter wet.
- Backfill with open, mineral substrate; avoid rich composts.
- Water to settle, then keep barely moist; never waterlog.
Provide overhead protection from persistent summer rain in humid districts to reduce rot.
Ecological Role
Alpine Cushion Engineer
Massive, tight cushions trap heat and fine sediments, creating microhabitats for other alpine plants and invertebrates. The colony’s structure slows wind at the surface and reduces frost heave around seedlings.
Uses & Significance
A Master of Alpine Adaptation
- Ecological Adaptation: The Vegetable Sheep (Raoulia eximia) is a remarkable example of extreme adaptation to harsh alpine and subalpine environments. Its dense, cushion-like growth and woolly foliage are crucial for protecting it from strong winds, cold temperatures, and intense solar radiation, while minimizing water loss.
- Habitat Creation: The compact form of the Vegetable Sheep provides microhabitats and shelter for small soil invertebrates, contributing to the biodiversity of its alpine ecosystem. The peat-like material formed from its old, rotted leaves acts as a sponge, retaining moisture and providing warmth to the living parts of the plant.
- Botanical Curiosity: Its striking resemblance to woolly sheep makes it a botanical curiosity and a memorable feature of the New Zealand alpine landscape. It is a testament to the unique evolutionary paths taken by plants in isolated environments.
- Horticultural Interest: While challenging to cultivate outside its natural habitat, Raoulia eximia is of great interest to alpine garden enthusiasts and botanists. It requires specialized conditions, often grown in alpine houses, to replicate its native environment.
- Pollinator Attraction: Despite their small size, the numerous flowers produced by Raoulia species attract various pollinating insects, such as bumblebees and hoverflies, playing a role in the alpine food web.
- Longevity: Individual Vegetable Sheep plants can be incredibly long-lived, with some specimens of Raoulia eximia living for over a hundred years and growing to more than a meter in diameter, showcasing their resilience.
Landscaping Ideas
Alpine Feature
Use vegetable sheep to anchor alpine scree beds and raised rock gardens. Provide maximum sun, excellent drainage, and lean, mineral soils; pair with Celmisia, Hebe cushions, and small alpine grasses.
Seasonal Care
Vegetable Sheep (Raoulia eximia) requires specialized care to mimic its harsh, well-drained, and cool alpine environment. Its unique adaptations mean that typical gardening practices may need to be adjusted to ensure its survival and health.
Spring
- Planting & Propagation: Spring is an ideal time for planting new specimens or propagating via seeds or division. Ensure the planting site has excellent drainage.
- Watering: After planting, water thoroughly but sparingly, maintaining a cool root zone. Consistent moisture is important as new growth begins, but avoid waterlogging.
- Air Circulation: Ensure good air circulation around the plant to prevent fungal issues.
Summer
- Sunlight Protection: Protect the plant from the harshest afternoon sun, especially in warmer climates, to prevent scorching.
- Watering: Maintain consistent moisture with careful watering, allowing the soil to dry slightly between waterings. Remember its preference for arid conditions and excellent drainage.
- Air Circulation: Continue to ensure good air circulation to combat any humidity.
Autumn
- Drainage: As temperatures begin to drop, ensure the plant's drainage remains optimal to prevent water accumulation that could lead to rot during colder, wetter months.
- Watering: Reduce watering frequency as the plant's growth slows and evaporation decreases.
Winter
- Frost Tolerance: Vegetable Sheep are frost-tolerant and adapted to cold alpine conditions.
- Protection: Provide protection from extreme, drying winter winds if your climate is particularly harsh, though their woolly leaves offer natural insulation.
- Watering: Water very sparingly, only when the soil is dry, as the plant is dormant and highly susceptible to root rot in cold, wet conditions.
Pruning
Techniques and Timing
Raoulia eximia, the Vegetable Sheep, generally requires very little to no pruning due to its naturally compact, cushion-forming growth habit. Its unique form is an adaptation to its harsh alpine environment, and excessive pruning can be detrimental.
- Minimal Intervention: The plant's dense, tightly packed structure is crucial for its survival. Avoid any significant structural pruning.
- Remove Dead Material: Occasionally, inspect the cushion for any dead or decaying plant material, especially in the crevices. Carefully remove these to prevent fungal growth and improve air circulation within the cushion.
- Timing: If any minor tidying is necessary, it is best done in spring as the plant begins its active growth phase.
- Avoid Damage: Be extremely gentle when handling the plant, as its dense structure can be surprisingly fragile if disturbed.
How to Grow Vegetable Sheep
Vegetable Sheep (Raoulia eximia), also known as Tuthuna, is one of New Zealand's most distinctive alpine plants, forming enormous woolly cushions that from a distance can resemble sleeping sheep. This remarkable cushion plant grows slowly in the harsh alpine environments of the South Island, creating dense mats covered in silvery woolly leaves. It's an iconic symbol of New Zealand's unique high-country flora. Due to its extreme specialization and slow growth, cultivating Vegetable Sheep is highly challenging and generally only recommended for experienced alpine plant enthusiasts or specialized botanical gardens. The focus should always be on replicating its natural, harsh alpine conditions as closely as possible.
From Seed
Propagating Raoulia eximia from seed is possible but extremely challenging due to its extremely slow growth rate and specific germination requirements. A specimen grown from seed can take 15 years to reach just 10 cm in diameter, highlighting the patience required. Successful germination and growth necessitate careful control of environmental conditions, meticulously mimicking its natural alpine habitat. Seeds should be collected fresh from mature plants and sown onto a very free-draining, sterile medium, such as a mix of fine grit and sand, without covering them. A period of cold stratification (e.g., several months in a refrigerator) is often required to break dormancy. Maintain consistent, but not excessive, moisture and provide bright, indirect light with excellent air circulation. Germination can be erratic and prolonged, often taking many months or even years. Due to these difficulties, seed propagation is typically undertaken by specialist nurseries or research institutions for conservation purposes.
By Division
Division is another method of propagation, but it is also challenging and requires extreme care to avoid damaging the plant. This method involves carefully lifting a portion of the cushion during the cool season (early spring or late autumn) and dividing its clumps with a very sharp, clean tool. Each division must have a healthy section of the cushion and a viable root system. Replant the divisions immediately into a prepared site with exceptionally well-drained, gritty soil, ensuring good air circulation around the plant. Water sparingly after replanting and protect from excessive moisture until new growth is evident. Due to the slow growth and delicate nature of the cushion, this method has a high risk of failure and should only be attempted by experienced cultivators.
Pests & Diseases
Resilience in a Harsh Environment
Raoulia eximia, the Vegetable Sheep, is remarkably resilient and well-adapted to its harsh alpine environment. Specific insect pests or plant diseases (such as fungal, bacterial, or viral infections) directly targeting this species are not widely documented as significant threats.
- Browsing Animals: In its natural habitat, browsing by introduced animals can pose a threat, particularly through trampling in high mountain environments.
- Environmental Stress: The primary challenges for Vegetable Sheep stem from environmental factors. Poor drainage or excessive moisture, especially in winter, can lead to root rot. Maintaining excellent drainage is crucial for its health.
- Human Impact: Trampling by hikers and other recreational activities can cause severe and irreparable damage to these fragile alpine plants.
- Climate Change: Broader threats like climate change, leading to rising temperatures and changes in habitat, are long-term concerns for alpine species like Raoulia eximia.
- Weed Competition: Invasive weed species can outcompete native alpine plants for resources, though this is less of a direct disease threat.
Cultural Significance
Raoulia eximia, commonly known as tutāhuna in Māori and "vegetable sheep" in English, holds cultural significance primarily due to its distinctive appearance. Its common name, "vegetable sheep," stems from its resemblance to sheep when viewed from a distance. The plant forms dense, hard, cushion-like masses with small, woolly, grey to grey-green leaves, contributing to this sheep-like illusion. Botanist Leonard Cockayne even remarked that its firm, convex shape makes "an excellent and appropriate seat for a wearied botanist." The Māori name "tutāhuna" is also widely used for this unique flora.
Bonus Tip
In humid districts, give vegetable sheep a simple rain-shed or plant on a steep scree mound to shed water. Refresh the gravel top-dress annually to keep the cushion surface clean and free of moss.
