Myrtle rust has been detected in a small number of plants at a nursery in the Waikato town of Te Kuiti.
This brings the total number of positive cases of myrtle rust to 16.
Two were originally recorded in Kerikeri, and the remaining 13 are in Taranaki.
The new location was found by tracing sales of plants from another nursery which tested positive for the fungus.
The Ministry for Primary Industries has received 420 reports of suspected myrtle rust to its 0800 line.