Carmichaelia australis
Carmichaelia australis is a New Zealand native broom (Fabaceae) notable for its leafless or sparsely-leaved, green, photosynthetic stems and showy pea-flowers (usually white to purple-tinged). A nitrogen fixer adapted to dry, open habitats such as river terraces, stony ground and light soils, it is valuable for restoration and low-maintenance gardens in sunny sites. native shrubs
Image credit: Native Broom (Carmichaelia australis). Wikipedia
| Scientific Name | Carmichaelia australis |
|---|---|
| Height | 1–3 m (occasionally taller in ideal sites) |
| Spread | 1–2 m, often upright to arching habit |
| Water Needs | Low once established; drought-tolerant |
| Light | Full sun (best flowering) to light shade |
| Frost Tolerance | High; suited to inland climates |
| Salt Tolerance | Low to moderate |
| Growth Rate | Moderate |
| Lifespan | Long-lived shrub |
Performs best in temperate regions with free-draining soils and full sun. Naturally found in drier areas, coping well with wind and summer dryness after establishment.
| City | Climate Suitability |
|---|---|
| Whangārei | Moderate |
| Auckland | Moderate |
| 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 |
Thrives in free-draining, low to moderately fertile soils.
Requires good light for strong growth and flowering:
Drought-tolerant after establishment:
Generally minimal pruning. Remove dead or tangled stems; tip-prune lightly to maintain shape. Avoid cutting hard into old wood.
Autumn or spring planting helps establishment in most regions.
Part of the distinctive New Zealand native brooms (Carmichaelia spp.), adapted to open, dryland and river terrace ecosystems. Useful in ecological restoration as a pioneer and soil improver.
Combine with divaricating shrubs and tussock grasses for authentic dryland plantings; group plantings create better wildlife refuge and visual impact.
These New Zealand brooms share drought tolerance, sun‑loving habits, and a role as pioneering, nitrogen‑fixing shrubs in dryland ecosystems. Combine several species to build resilient, wildlife‑friendly plantings on free‑draining sites.
Learn more about native shrubs in Cultural Plants.
Carmichaelia australis is a leafless, twiggy broom forming open shrubs with flattened, photosynthetic stems (cladodes) and small, pea‑like flowers set close to stems. The architecture minimises water loss in dry sites and creates a distinctive, architectural silhouette.
Occupies river terraces, stony flats, and dry scrub from coastal to inland sites, typically on freely draining, low‑fertility soils with high light and airflow.
A nitrogen‑fixing legume that improves poor soils and pioneers open, drought‑prone habitats. Flowers support insects; seeds are dispersed near the parent, gradually forming small colonies in suitable sites.
Functions as a framework shrub in dryland restoration, providing shelter for grasses and divaricating shrubs and enriching soil via symbiotic nitrogen fixation.
Minimal inputs; do not over‑fertilise. Water through the first dry summer; thereafter, only in extended droughts. Mulch lightly with gravel or coarse bark to suppress weeds.
Prune lightly after flowering to shape; avoid hard cuts into old wood. Check for scale on stressed plants and improve airflow if needed. Keep base weed‑free to reduce competition.
Ideal for dry gravel gardens, banks, and river‑themed plantings. Pairs naturally with divaricating shrubs, Olearia, and native tussocks for authentic dryland assemblages.
Status varies regionally; use eco‑sourced plants for restoration. Protect from browsing during establishment and manage weeds to ensure recruitment.
Mākaka appear in whakataukī and regional traditions, reflecting nuanced relationships with these hardy shrubs of open country. Today, Carmichaelia species are valued for drought resilience and for supporting native pollinators in dryland restoration.
The genus Carmichaelia holds complex cultural significance in Māori tradition, with the common name "mākaka" reflecting indigenous knowledge of these distinctive broom-like shrubs. Interestingly, traditional Māori perspectives on some species were cautionary, with the saying "E rito koe ki te taunoka" comparing a person without heart to these plants. This linguistic heritage indicates that tangata whenua developed nuanced cultural meanings associated with different Carmichaelia species across various tribal regions.
