Poa colensoi
Blue Tussock, also known as Colenso's Poa, is a distinctive New Zealand endemic grass that forms small, compact tussocks with beautiful blue-green to blue-grey narrow leaves that create tight, dense clumps rising 5-70cm tall. Named after the pioneering missionary-botanist William Colenso, this hardy native produces delicate arching flower stems that rise just above the foliage, bearing open arrangements of bronze flower heads in spring. Particularly prominent in Otago's low tussock grasslands, it has been recognized as the native grass species with the highest potential for high-altitude livestock systems due to its excellent palatability and above-average regrowth rates, while also serving as an outstanding rock garden plant and erosion control species. native grasses
Image credit: Blue Tussock (Poa colensoi). Wikipedia
| Scientific Name | Poa colensoi |
|---|---|
| Height | 0.05-0.7 meters (typically 0.3-0.45m) |
| Spread | 0.3-0.6 meters |
| Water Needs | Low to moderate (drought-tolerant) |
| Light | Full sun to light shade |
| Frost Tolerance | Excellent (high-altitude native) |
| Salt Tolerance | Not specified |
| Growth Rate | Moderate (good regrowth rates) |
| Lifespan | Long-lived perennial |
Blue Tussock is adapted to cool-season conditions and performs best in temperate to subalpine climates. It is particularly prominent in Otago and other South Island regions but can adapt to suitable conditions throughout New Zealand.
| City | Climate Suitability |
|---|---|
| Whangārei | Moderate |
| Auckland | Moderate |
| Hamilton | Good |
| Tauranga | Moderate |
| Rotorua | Good |
| Gisborne | Good |
| New Plymouth | Good |
| Napier | Ideal |
| Whanganui | Good |
| Palmerston North | Good |
| Wellington | Ideal |
| Nelson | Ideal |
| Christchurch | Ideal |
| Dunedin | Ideal |
| Invercargill | Ideal |
Blue Tussock adapts to various soil conditions:
Adaptable to various light conditions:
Low to moderate water needs:
This versatile native plant offers multiple practical applications in landscaping and garden design, from providing ground cover and erosion control to creating habitat for native wildlife. The plant's natural characteristics make it valuable for restoration projects and sustainable gardening practices.
Blue Tussock requires minimal maintenance:
The compact, neat growth habit requires minimal intervention, with the main maintenance being the annual removal of old foliage to showcase the attractive blue-green color.
The best time to plant Blue Tussock is during spring or early autumn when cool-season growth conditions are optimal.
Choose a site with:
Minimal watering during the first season. Once established, this extremely hardy grass requires virtually no care and thrives on neglect.
Growing Blue Tussock from seed:
Division is effective for established tussocks:
Blue Tussock has potential for wider cultivation due to its excellent ornamental qualities and low maintenance requirements.
Blue Tussock (Poa colensoi) honors one of New Zealand's most important early botanical explorers and represents the country's cool-season grass heritage:
Today, Blue Tussock serves as both a memorial to early botanical exploration and a practical example of how native plants can serve multiple purposes - from ornamental rock garden use to sustainable high-altitude grazing systems.
Provide well-draining soil and avoid overwatering or over-fertilizing. This exceptionally hardy grass thrives on harsh conditions and rarely requires any pest or disease management when grown in appropriate sites.
Blue Tussock is perfect for creating low-maintenance, water-wise landscapes that capture the essence of New Zealand's tussock grasslands in compact form. Plant it in rock gardens where the distinctive blue-green color provides excellent contrast against stone, or use it for erosion control on slopes where its compact, dense growth habit prevents soil movement. The annual raking of old leaves is actually beneficial - it prevents the buildup of dead material and showcases the beautiful fresh growth. Try mass plantings at different heights to create texture variation while maintaining the neat, controlled appearance.
Learn more about New Zealand's tussock grassland heritage in Grasses & Flaxes.
This section provides important information about plant care and cultivation practices. Understanding these aspects helps ensure successful growth and development in garden conditions.
This section provides important information about plant care and cultivation practices. Understanding these aspects helps ensure successful growth and development in garden conditions.
This section provides important information about plant care and cultivation practices. Understanding these aspects helps ensure successful growth and development in garden conditions.
This section provides important information about plant care and cultivation practices. Understanding these aspects helps ensure successful growth and development in garden conditions.
Blue tussock plays specialized ecological roles in New Zealand's montane and inland grasslands, where its distinctive growth form contributes to grassland diversity and provides habitat for specialized grassland organisms. The plant helps create the structural complexity that characterizes healthy tussock grassland ecosystems, while its specific habitat requirements contribute to the environmental gradients that support diverse grassland communities. Its presence helps maintain the ecological integrity of native grassland systems.
This section provides important information about plant care and cultivation practices. Understanding these aspects helps ensure successful growth and development in garden conditions.
This section provides important information about plant care and cultivation practices. Understanding these aspects helps ensure successful growth and development in garden conditions.
Blue tussock faces conservation challenges from habitat modification, competition from invasive grasses, and changes in land management that can affect its specialized grassland habitat. The species' specific environmental requirements and the widespread modification of New Zealand's grassland environments make conservation important for maintaining grassland biodiversity. Conservation efforts focus on protecting natural grassland habitats, managing invasive species, maintaining appropriate grazing regimes, and preserving the environmental conditions essential for diverse native tussock grassland communities.
This plant has cultural associations in Aotearoa and is valued in restoration and gardens for ecological services; use eco‑sourced stock near natural areas.
Blue tussock was recognized by Māori as part of the diverse grassland communities that characterized inland and mountain environments, contributing to the complex landscape mosaics that supported traditional resource management and seasonal activities. The plant's distinctive blue-green coloration and growth form made it recognizable among tussock grasses, while its presence indicated specific environmental conditions in traditional ecological knowledge. The species continues to hold cultural interest as part of New Zealand's diverse tussock grassland heritage.
This section provides important information about plant care and cultivation practices. Understanding these aspects helps ensure successful growth and development in garden conditions.
This section provides important information about plant care and cultivation practices. Understanding these aspects helps ensure successful growth and development in garden conditions.
