Haast's Mountain Daisy (<i>Celmisia haastii</i>) hero image

Haast's Mountain Daisy

Celmisia haastii

Not Threatened

This native plant, known as Haast's Mountain Daisy (scientific name: Celmisia haastii), 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 Alpine Plants.

Haast's Mountain Daisy (<i>Celmisia haastii</i>) showing its low-growing patches of grey-green foliage and white daisy-like flowers in an alpine setting
Image credit: Haast's Mountain Daisy (Celmisia haastii) - photo by Wikipedia contributors, via Wikipedia

Plant Description

Celmisia haastii, commonly known as Haast's Mountain Daisy, is a distinctive perennial subshrub endemic to the South Island of New Zealand. This low-growing, branching plant forms small to large patches of grey-green, leathery leaves that are often covered in a fine tomentum, giving them a slightly silvery sheen. It is well-adapted to the harsh conditions of its alpine home, capable of withstanding strong winds, intense sunlight, and cold temperatures. In summer, it produces charming white daisy-like flowers with yellow centers, held singly on short stalks above the foliage, adding a touch of delicate beauty to the rugged landscape.

Quick Facts

Celmisia haastii quick facts
Scientific Name Celmisia haastii
Height 0.05-0.15 metres
Spread 0.50-1.0 metre
Water Needs Moderate; requires consistent moisture but dislikes waterlogging
Light Full sun
Frost Tolerance Very High (Alpine hardy)
Salt Tolerance Low
Growth Rate Slow
Lifespan 10-25 years

Climate Best Suited to

Haast's Mountain Daisy is a robust alpine specialist, thriving in the cool, crisp air of the montane to subalpine zones of the South Island. It is exceptionally hardy to severe frosts, snow, and strong winds. It is crucial to replicate these conditions in cultivation, ensuring good air circulation and protection from prolonged summer humidity. In lowland gardens, excellent drainage and a well-ventilated spot are essential for its long-term health.

Regional Suitability

City suitability for Haast's Mountain Daisy
City Climate Suitability
Auckland Poor (too hot and humid)
Wellington Marginal (needs very good drainage)
Christchurch Good
Dunedin Excellent
Invercargill Excellent

Plant Habitat

Endemic to the South Island, Celmisia haastii is found from North Canterbury southwards, typically inhabiting montane to alpine grasslands, herbfields, and rocky places. It is often found in sites where snow lies late into the season, indicating its preference for cool, moist conditions during the growing period. Its deep root system helps it anchor firmly in unstable, gritty substrates, making it a key pioneer species in these challenging environments.

Growing Requirements

Soil Requirements

Demands moist, yet exceptionally well-drained and gritty soil. It is very sensitive to poor drainage, which can quickly lead to root rot.

  • Moist, very gritty, free-draining soil
  • Stony or scree-like substrates
  • Excellent aeration is critical

Light Requirements

Demands full sun for best health, compact form, and flowering. It will become sparse and less vigorous in shaded conditions.

  • Full sun essential
  • Avoid shade
  • Needs bright, open exposure

Water Requirements

Needs consistent moisture, particularly during its active growth phase. While it tolerates occasional dry spells, prolonged drought will stress the plant.

  • Consistent moisture, but never soggy
  • Water deeply and infrequently
  • Intolerant of prolonged drought or waterlogging

Planting and Establishing

To plant Haast's Mountain Daisy, choose a site that provides perfect drainage, such as a rock garden, scree bed, or a very free-draining raised bed. Incorporate abundant grit, scoria, or coarse sand into the planting mix. Plant the daisy with its crown slightly elevated above the surrounding soil level and top-dress with a generous layer of fine gravel to prevent moisture accumulation around the base and encourage good air circulation. Water thoroughly upon planting and maintain consistent moisture during establishment.

Ecological Role

Celmisia haastii plays a vital role in stabilizing alpine soils and contributing to the biodiversity of high-altitude grasslands, providing shelter and food for specialized alpine fauna.

Uses & Significance

Garden Uses

A highly sought-after plant for alpine gardens, scree beds, and containers, where its unique foliage and charming flowers can be admired.

  • Alpine and rock gardens
  • Scree beds and raised planters
  • Container gardening

Ecological Value

Its flowers provide nectar for native alpine insects, including butterflies and moths, which are important pollinators in these often-barren environments.

  • Nectar source for alpine pollinators
  • Habitat for small invertebrates
  • Soil stabilization in exposed areas

Landscaping Uses

Ideal for specialized landscaping projects aiming to replicate a true New Zealand alpine aesthetic. Its architectural form makes it a striking feature plant.

Seasonal Care Calendar

Spring

Remove any dead or damaged foliage from the previous winter to promote air circulation and prevent fungal issues. A very light, low-nitrogen feed can be given if needed.

  • Clear winter debris
  • Check for signs of rot
  • Light low-nitrogen feed

Summer

Monitor soil moisture carefully, ensuring it remains consistently damp but not wet. Ensure good air circulation, especially during warmer, humid periods.

  • Maintain consistent moisture
  • Ensure good air flow
  • Watch for aphids and mites

Autumn

After flowering, spent flower stalks can be removed for neatness. Prepare the site for winter, ensuring drainage remains excellent to prevent waterlogging.

  • Remove spent flower stalks
  • Check drainage for winter
  • Refresh gravel top-dressing

Winter

Requires minimal attention during winter. It is exceptionally frost-hardy and benefits from snow cover, which insulates it from extreme cold.

  • Minimal intervention
  • Ensure protection from excessive wetness
  • Resistant to cold and snow

When to Prune and How Much

Pruning is typically limited to removing spent flower stalks and any dead or yellowing leaves from the rosettes to maintain plant health and prevent rot.

  • Remove spent flower stalks
  • Tidy dead or yellowing foliage
  • Avoid cutting into the main rosette

Always use sterilized, fine-pointed tools to avoid introducing pathogens and for precision around the tight foliage.

How to Grow Haast's Mountain Daisy

Cultivating Haast's Mountain Daisy (Celmisia haastii) 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 Haast's Mountain Daisy 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.

Haast's Mountain Daisy can be grown from fresh seed, but it requires specific conditions for successful germination. Collect fresh seeds when ripe in late summer.

  1. Sow on the surface of a very gritty, free-draining seed mix.
  2. Keep moist and in a cold frame.
  3. Germination can be slow and irregular.
  4. Grow on carefully in individual pots.

Providing natural winter chilling can aid germination, and protecting young seedlings from excessive moisture is critical.

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.

Hardwood cuttings can be taken, but success rates can be variable and establishment is slow.

  1. Take small, firm cuttings in late spring to early summer.
  2. Dip in strong rooting hormone powder.
  3. Insert into a very gritty, well-aerated propagation mix.
  4. Provide bottom heat and ensure high humidity.

Additional Methods

Depending on the growth habit of Haast's Mountain Daisy, 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 is not typically recommended as it can be very stressful for this slow-growing plant.

  1. Avoid division unless absolutely necessary.
  2. If attempting, divide in early spring with extreme care.
  3. Ensure each division has a substantial root system.

Pests & Diseases

Highly susceptible to root and collar rot if drainage is poor or conditions are too humid. Aphids can sometimes be a problem on new growth. Ensure excellent drainage and good air circulation to prevent issues.

Cultural Significance

Haast's Mountain Daisy is valued by alpine plant enthusiasts for its unique silver foliage, representing the specialized adaptations of New Zealand's high-country flora.

  • Prized by alpine plant collectors
  • Represents unique alpine adaptations
  • Endemic to the South Island

Bonus Tip

To achieve the best silvery colour and compact form, ensure your Haast's Mountain Daisy receives maximum sunlight and impeccable drainage, mimicking its high-country habitat.

Plant Conservation

Celmisia haastii is currently classified as "Not Threatened" in the New Zealand Threat Classification System. It is widespread in suitable habitats across the South Island. However, like many alpine species, it is vulnerable to habitat degradation from recreational activities, browsing by introduced animals, and the impacts of climate change on its specialized high-country environments.