Myrtle Rust has been found on another two horticultural properties in Taranaki.

It brings the total number of known infestations to five.

The first confirmed cases were at a nursery and an adjoining property in Kerikeri, and a plant nursery in Waitara.

MPI's David Yard said today's two confirmed cases are in another nursery in Waitara, and at a garden centre in downtown New Plymouth.

He said the new finds are disappointing but not unexpected.

The Ministry expects to continue to find new infections, given it's most likely scenario that the fungal spores were blown to New Zealand from Australia during a major weather event.