Welwitschia is a monotypic genus of succulent plant, consisting exclusively of the very odd Welwitschia mirabilis Hook. f.
Welwitschia is the only genus of the family Welwitschiacae, in the order Gnetales, in the class Gnetopsida.
This is a desert plant which grows from a short, thick trunk, with only two leaves that continuously grow from their base, and a long, thick taproot. Shortly after germination, the apex of the plant dies, leaving the cotyledons to continue to grow. The species is dioecious.
The age of these plants is difficult to assess, but it's believed that they are very long-lived, possible living to one thousand years or longer. Certain individuals are thought to be in excess of 2000 years of age.
The plant is thought to absorb water through peculiar structures on the leaves, harvesting moisture from the dew that comes into the desert every night. Named after Dr. Friedrich Welwitsch, it is generally considered to be one of the oddest plants in existence. Although considered endangered due to its very slow growth and the fact that older plants are desired by collectors, a fair number of plants exist in the wild. The plants existing in Angola are generally considered to be better protected than the plants in Namibia as a function of the relatively high concentration of landmines in Angola.
The species grows readily from seed, which may be purchased from specialty seed dealers. It must be kept moist for the first couple of weeks, and exposed to as much heat and light as possible during this time. Seeds collected from the wild are heavily contaminated with spores of Aspergillus niger, which causes them to rot shortly after they germinate. Seeds from the Kirstenbosch National Botanical Garden in Cape Town, South Africa, or other cultivated sources, are much cleaner and less likely to rot.