It has 72,000 items, making it the second largest herbarium in the South Island.

The herbarium was established in 1946 by botanist Geoff Baylis.

[1] As of 2020, the vascular plant, bryophyte and lichen collection is curated by Janice Lord, and the fungal and slime mold collection by David Orlovich.

[4][2][5] Professor Alan Mark contributed many of the specimens of alpine flora in the vascular plant collection.

[2] The herbarium also houses the collection and voucher specimens belonging to botanical illustrator Audrey Eagle, used to illustrate the two volumes of Eagle's Complete Trees and Shrubs of New Zealand.