Welwitschia Mirablilis: An Extraordinary Plant

This tangled mess of tattered and withered leaves has been called one of the ugliest plants in the world. While it certainly isn’t pretty, it definitely is one of the most remarkable members of the Plant Kingdom.

Welwitschia mirabilis grows only in the arid deserts of Namibia and Angola. When it was discovered in 1859 by Austrian physician and botanist Friedrich Welwitsch, he was so overwhelmed by the plant that he "could do nothing but kneel down and gaze at it, half in fear lest a touch should prove it a figment of the imagination.”

Welwitschia mirablilis is unusual because the entire plant is comprised of just two leaves —just two, along with a stem base and roots. The pair of leaves are the original baby leaves it grew when the plant was a seedling. The leaves continue to grow like fingernails, never shedding, while their tips get worn off with age and abrasion. The leaves rest on the ground and as they grow, their ends get split, torn and tattered into multiple ribbons, which gives the impression that there are multiple leaves. Many of these plants are over 1,000 years old.

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Welwitschia mirablilis, the most remarkable plant, looks like a mess. Photo credit: Hans Hillewaert/Wikimedia

Welwitschia mirablilis is a very lonely plant. It’s the only surviving species of its genus, the only genus of its family, and the only family of its order. Welwitschia belonged to a group of plants that thrived 140 millions years ago, at the time of the dinosaurs. Over time, all of its relatives slowly disappeared, but Welwitschia remained.

Welwitschia mirablilis grows extremely slowly and can reach a height of 1.5 meters above the ground, although the majority of specimens are less than a meter tall. The leaves grow an average 8 to 15 centimeter per year. A thousand-year-old plant can therefore produce up to 150 meters of leaf tissue, although leaves longer than 4-6 meters are seldom seen in living plants as the tips continue to die and wither. Some of the largest specimens can be 4 meters across.

The leaves of the Welwitschia mirablilis are very thick, about 1.4 cm, that helps keep the soil under the plant cool and moist, which is essential for the plant’s survival in the desert. Since rainfall in this area is erratic, the plant absorbs moisture from fog that regularly develops at night over the desert when the cold north-flowing currents meets the hot air coming off the Namib Desert. This function is performed by the leaves by keeping their stomata open at night and closing it when the fog lifts. Because of the dependence on fog, the plant is seldom found more than 100 km from the coast.

Welwitschia mirabilis provides an important source of food to animals such as oryx, springbok, zebra, and black rhino in times of extreme drought. The plant also provides shade to snakes and lizards.

Welwitschia mirabilis is neither endangered nor threatened, although there is evidence of fungal infection that is known to adversely affect reproduction. The plant is protected under law and within a system of national parks and communal conservatories in Namibia and Angola. In recent years, Welwitschia has become increasingly important as a tourist attraction.

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