The KwaZulu Natal Herbarium was established in 1882 and has acquired National Monument status. It is a centre for the study of the indigenous plants of the eastern region of South Africa. This region includes three of the IUCN internationally recognized centres of plant diversity. The main focus of the work is on the herbarium collection, which consists of five key areas: plant information services, systematic research, documentation of the flora, computerized storage of the collection, student training and promoting botany in the community. The Ethnobotany Unit, managed by Prof. Neil Crouch is based at the Herbarium.

The KwaZulu-Natal Herbarium had a good jump start in 1882, its founder John Medley Wood arranged for the storage of more than one thousand five hundred specimens to the collection. Back then Wood was the Curator of the Durban Botanic Gardens which had been already been opened since 1849. He regarded the herbarium as a necessity that would make the establishment an authentic botanic garden. Supported by the governor of the colony, Sir Henry Bulwer a keen and common interest in the garden and the herbarium specimens was shared. The Colonial Government gained the responsibility of the herbarium specimens, and under the Curatorship of Wood, the Colonial Herbarium was born. After thirty three years of under Wood, he built up the collection of specimens and the library. Of the thirteen thousand specimens prepared by Wood, only about six thousand specimens remain in the collection today.

Due to lack of funds the Durban Agricultural and Horticultural Society, who owned the garden, collapsed, and in 1913 most of the garden was handed over to the Durban Municipality. About five thousand square meters, which included the Herbarium and Medley Wood's house was excluded at that time and given to the Union Department of Agriculture, the next year. When Medley Wood died in 1915, the main focus for almost the next fifty years shifted to plant The early 1960's saw the departure of the last pathologists, and the herbarium's systematic studies of the KwaZulu-Natal flora took a new lease on life. A few years later ecological studies were added to the Unit.

The collections are housed in an Edwardian building which was built in 1902, in what once formed part of Durban Botanical Garden . The Herbarium and Medley Wood House, have both been declared Heritage buildings. Many of the cabinets at the herbarium are made of Kiaat ( Pterocarpus angolensis ) to a design dated 1955, and there are also a few of Medley Wood's original Victorian cabinets, as well as some modern steel ones of various designs. Specimens are arranged according to the Engler system as employed in the List of Southern African Plants generated by PRECIS. There are about one hundred and twenty thousand specimens, mainly from KZN , but also from surrounding areas.