Hantam National Botanical Garden
Institution Code: SAHNG
BGCI Member: Yes
About the Hantam National Botanical Garden
South Africa’s ninth national botanical garden was established on the outskirts of Nieuwoudtville in the western Karoo, Northern Cape, South Africa, in August 2007. The new garden, known as the Hantam National Botanical Garden since it was formally gazetted in December 2008, was established on the farm Glenlyon (managed over several decades by the renowned conservation farmer Neil MacGregor) and is now managed by the South African National Biodiversity Institute (SANBI) as part of South Africa’s network of national botanical gardens. ‘Hantam’ is most probably derived from the Khoekhoe heyntama, the name for the edible tubers of some species of Pelargonium.
This wild Garden comprises over 6,000 ha on several portions of land, not all contiguous, on the Bokkeveld Plateau, and is world-renowned for its incredible diversity of bulbous plants. Some 40% of the flora comprises bulbs, creating spectacular displays in autumn and spring each year. The Garden also includes large natural patches of renosterveld fynbos (both shale and dolerite renosterveld) and succulent karoo (formally known as Hantam Karoo) vegetation. Owing to the rich diversity and density of bulbs, Nieuwoudtville’s biodiversity is of international significance and as a botanical hotspot of global significance; the town is often referred to as ‘the bulb capital of the world’.
From west to east, the vegetation types in the Garden comprise Nieuwoudtville Shale Renosterveld, Nieuwoudtville-Roggeveld Dolerite Renosterveld and Hantam Karoo. The Nieuwoudtville Shale Renosterveld is an endangered vegetation type in South Africa, almost 60% of which has been transformed through cultivation. The Nieuwoudtville-Roggeveld Dolerite Renosterveld occurs on dolerite ridges and the surrounding plains east of the Bokkeveld Plateau. The vegetation of the dolerite plains is unique in being almost devoid of shrubs or perennial grasses. Geophytes and annuals comprise 90% of the cover and 80% of the species. In addition to threats from habitat transformation, resulting in fragmentation of the natural veld, Nieuwoudtville’s unique biodiversity associated with these two vegetation types is also threatened by invasive alien plants, especially naturalized annual grasses (such as the Common Wild Oat Avena fatua, Japanese Brome Bromus pectinatus, Small Canary Grass Phalaris minor and False Barley Hordeum murinum) and is predicted to be affected by global climate change.
Further east, the Hantam Karoo (part of the Succulent Karoo Biome) comprises dwarf Karoo shrubland with nearly equal proportions of succulents (Aloe, Antimima, Euphorbia, Ruschia) and low karroid shrubs, particularly of the daisy family Asteraceae (Eriocephalus, Pentzia, Pteronia). The area has rich displays of spring annuals and geophytes. Hantam Karoo is an arid area with a mean annual rainfall of 190 mm (compared with 350 mm around Nieuwoudtville), with a clear peak from June to July and hardly any rain in December and January—characters typical of a winter-rainfall regime.
All three vegetation types are visible in the southernmost portion of the Hantam Garden, which is accessible to visitors either on foot or through the guided bus tours offered during the spring season.
Part of SANBI’s vision for the Hantam Garden in Nieuwoudtville is that it will provide an important conservation area for the region which will be used by SANBI to promote nature-based tourism, the conservation of the area’s unique biodiversity, environmental education opportunities and long-term ecological research and monitoring, similar in concept to the Gobabeb Training & Research Centre in the Namib Desert, Namibia.
Climate change models indicate that fynbos and succulent karoo have expanded and contracted with respective wet and dry climatic cycles and the area around Nieuwoudtville has been identified as an important site for monitoring shifts in succulent karoo vegetation in response to climate change. The southernmost distributions of the Kokerboom (Aloe dichotoma) can be found within walking distance of the remote northern parts of the Garden; the tree is showing signs of responding positively to recent warming trends by expanding its populations in this area. This is in contrast to its sister populations in Namibia and the Orange River Valley, where recent warming seems to have exceeded critical temperature limits for this species and where it is dying back.
The new National Botanical Garden aims to conserve existing biodiversity on the property rather than create large new cultivated areas of indigenous plants, and will serve as a centre for biodiversity research in the Succulent Karoo region and Bokkeveld Plateau. In managing the new Garden, SANBI works closely with local and regional stakeholders (including local and provincial government), bioregional programmes, conservation agencies, NGOs, universities and museums.
Hantam National Botanical Garden
PO Box 8
Northern Cape 8180 South Africa
Telephone: +27 (0)27 218 1200
Fax: +27 86 555 9082
Primary Email: Hantam@sanbi.org.za