tiny stonecrop of seasonally wet lowland ground
- Size
- Height: 1-3 cm, Spread: up to 10 cm
- Lifespan
- Perennial
- Diet
- Not applicable - autotrophic. Photosynthetic succulent ground cover. Obtains nutrients from damp, open soils.
- Habitat
- Damp, open areas, including riverbeds, lake margins, and wetlands. Prefers periodically moist soils. Tolerates temporary inundation.
- Range
- Endemic to New Zealand. Restricted to the Wairarapa region of the North Island. Found along the Ruamahanga River and nearby wetlands.
- Endemism
- Endemic
- Main Threats
- Habitat loss from river modification and wetland drainage. Climate change affecting water levels.
- Population
- Restricted range. Found only in the Wairarapa region of the North Island. Population small but stable. Not threatened.
- Conservation Status
- data_deficient
- Human Risk
- harmless
- Handling Note
- native succulent ground cover, safe to handle
- Conservation Note
- Endemic herb; data insufficient for full threat classification.
- Assessment
- NZTCS Vascular Plants (2023)
- Te Ao Māori
- Crassula ruamahanga has no recognised Māori name. It is a very local plant, found only in the Wairarapa. Its small size and restricted range meant it was likely not distinctively named. It is part of the flora of the Ruamahanga River.
Proper miniature. You will miss it unless you are looking down. Crassula ruamahanga, New Zealand pygmy stonecrop, is one of the smallest native ground covers. Its tiny leaves are packed tight on slender stems. The plant forms a low mat, barely noticeable among the stones and soil.
The leaves are small, narrow, succulent, dark green. The plant is a succulent, storing water. The flowers are tiny, white, star-shaped, appearing in summer. You need a hand lens to appreciate them.
Crassula ruamahanga grows in damp, open areas. Riverbeds. Lake margins. Wetlands. It likes periodic moisture. It tolerates flooding.
The name ruamahanga refers to the Ruamahanga River in the Wairarapa, where the plant was first collected. It is named for its home.
The species is endemic to New Zealand. It is found only in the Wairarapa. A very local plant.
Crassula ruamahanga is not threatened. Its range is small, but its habitat is stable. It is not common, but it is not rare.
The plant is a reminder. Some species have small ranges. They live in one valley, one river, one place. They are no less important for their obscurity.
NZ pygmy stonecrop is a miniature. A tiny succulent. A plant you could step on and never know. It does not mind. It has been there for a long time.