Cape Town 140828. Phakamani Xaba, senior horticulturist at Kirstenbosch Botanical Gardens next to an artwork by R. B Slingsby. The Gardens are marking their centenial celebrations with an art biennale which focuses on traditional and medicinal use of plants. reporter: John Yeld.Picture:Jason Boud

Cape Town - Concern about the unsustainable demand for indigenous medicinal plants, still used by an estimated 70 percent of South Africa’s 53 million people, is the focus of Kirstenbosch Biennale.

The biennale is an exhibition of botanical art by artists from southern African and elsewhere with the theme “Medicinal and traditional plants of southern Africa”. It officially opened last week as part of the national botanical garden’s centenary celebrations.

Phakamani Xaba, a research conservation horticulturist at Kirstenbosch, says the biennale highlights the rich history of traditional-plant use among indigenous people, while also aiming to raise awareness about unsustainable over-exploitation.

The people of southern Africa have used plants for food, medicine and rituals for several thousand years. At least 3 689 different plants have been used in traditional medicine in the region. Despite drastic changes in land use over the past two centuries, coupled with the advent of commercial agriculture and the introduction of exotic food plants, the use of traditional medicines remains high.

“The bulk of the demand for medicinal plants is from urban populations in a trade estimated to be worth R2.6-billion a year,” he says.

Most of these urban users live in poor township areas and have little contact with the natural environment. “In this context, harvesting plants in the wild is unsustainable, and many plants are being pushed towards extinction in the wild.”

Curator Nicki Westcott says the biennale’s theme of medicinal and traditional use plants is “suitably topical”.

“Despite the fact that some of the compounds derived from plants are now chemically generated, the exhibition highlights the increasing fragility of the supply of products deriving from the natural world.”

Westcott also says one of the curatorial aims of the exhibition is “to situate botanical art clearly within the domain of art”.

“For this reason, other artists have been invited and their work sets up a reverberating conversation with the botanical work.”

The main exhibition consists of four works from each of 54 artists, selected during a rigorous judging process by a distinguished panel of local botanists, botanical artists and art custodians. One of the highlights on display is the work of Cape-based Margaret de Villiers, who won a gold medal and “best on show” award at the annual Royal Horticultural Society’s Botanical Art show in London. - Cape Argus

l The exhibition, in the conference hall at the main entrance, is open to September 15.