Myrtle rust has been found on a hedge in Ōtautahi-Christchurch, the furthest south an established infection of the plant disease has been seen.
Myrtle rust has been spreading rapidly across the country since it was first identified in 2017, attacking plants in the myrtle family including pōhutukawa, mānuka, ramarama, rōhutu, rātā and swamp maire.
Bad infections can be deadly for the plants.
Manaaki Whenua Landcare Research said the disease was most frequently seen across the North Island and the top of the South Island.
Christchurch had generally been considered a low-risk environment for myrtle rust which thrived in warm, moist areas.
It said previous sightings of the disease in the Christchurch area had been on plants purchased in nurseries in other regions and relocated there. Canterbury Regional Council said biosecurity officers conducted a search after the recent detection but did not find any additional plants that were infected.
See RNZ's full article here.