This plant is forming large patches in an area of the Rimutakas. Initially I thought it was Mentha suaveolens from seeding material but now it has flowered it is not that species but looks to be another Lamiaceae. See link below. https://http://www.inaturalist.org/observations/8620083
Leaves
Teucrium scorodonia. Thx Colin
Correct - Teucrium scorodonia
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