climbs the coastal sand dune scrub

Size
Length: 500 cm
Lifespan
5–10 years
Diet
Photosynthetic climber. Draws energy from sunlight. Obtains nutrients from sandy or rocky soils in coastal environments.
Habitat
Coastal cliffs sand dunes forest margins scrub and disturbed areas. Prefers sandy or rocky soils with full sun to partial shade. Tolerates salt spray and wind.
Range
Throughout New Zealand from Northland to Stewart Island. Most common in coastal and lowland areas. Also found on Chatham Islands. Present in Australia and Pacific Islands.
Endemism
Endemic
Main Threats
Habitat loss from coastal development is primary threat. Competition from invasive exotic bindweed species. Climate change affecting coastal habitats.
Population
Populations considered stable in protected coastal areas. Species common on coastal cliffs and sand dunes throughout New Zealand. Threatened by competition from exotic bindweed.
Conservation Status
Not Threatened
Human Risk
harmless
Handling Note
native vine, safe to handle
Conservation Note
Endemic climber; widespread in coastal and lowland habitats throughout New Zealand.
Assessment
NZTCS Vascular Plants (2023)
Te Ao Māori
In Māori tradition kaihua was known for its flowers. Nectar was sometimes collected as sweet treat. Trailing stems were occasionally used for tying. Plant was recognised as native relative of more aggressive introduced bindweed. Presence on coastal cliffs noted as sign of stable sand dunes.
It does not inhabit the forest exclusively. Calystegia tuguriorum is native bindweed. Large white trumpet-shaped flowers. Grows on coastal cliffs sand dunes and forest margins. Often forms dense mats. Flowers open in morning and close in afternoon. Each flower lasts only single day. Flowers are up to 5 centimetres across. Five fused petals forming funnel shape. Brief bloom. Single day to be seen. Leaves are arrow-shaped or triangular. With pointed tip. Arranged alternately along stem. Stems are slender and trailing. Rooting at nodes where they contact soil. Allows plant to spread rapidly across open ground. Stabilising sand dunes and coastal soils. Plant that holds coast together. Species is similar to introduced exotic bindweed but has smaller flowers and less aggressive growth. Exotic bindweed or Calystegia sepium has larger flowers and thicker stems. Can smother native vegetation. Kaihua is more delicate plant. Rarely causing problems in natural ecosystems. Important stabiliser of coastal sand dunes. Roots holding sand in place while wind tries to blow it away. Name kaihua means food of the flower. Possibly referring to nectar. Nectar is sweet and was sometimes collected as treat. Small sweetness from small flower. Plant is not commonly cultivated but can be grown in coastal gardens. Thrives in sandy well-drained soil. On coastal cliff with salt spray in air and wind bending stems white flowers stand out against grey rock. Then afternoon comes and they close one by one. Until next morning when they open again. Short life. Single day. Then gone. No one told kaihua that day is not enough. It opens anyway. And that seems to be enough.