Zambia’s Endemic Gladioli

Gladioli, sometimes called Sword Lilies, are widely grown and admired for their showy, brightly coloured floral displays, particularly from the numerous horticultural hybrids that have been bred over the last century. The genus Gladiolus, in the Iridaceae family, is composed of approximately 300 species spread between southern Europe, Africa and into western Asia with its centre of diversity in the Cape Floristic Region of South Africa.

Above are some images of some colourful cultivated gladioli species.

In Zambia there are about 20 species with the most commonly observed being the Parrot-Beak Gladiolus, Gladiolus dalenii, which grows widely in the woodlands and savannas of sub-Saharan Africa. However, most of the Gladioli species in Zambia are not nearly as widespread, occurring in Zambia and several neighbouring countries, while two are narrow endemics, growing in Zambia and only one neighbouring country and two are full endemics, growing only in Zambia.

Of our two endemic Gladioli species, Gladiolus serenjensis was first collected in 1955 but not described until 1993 and named after Serenje District where the majority of collections have come from. It is a slender plant up to 50 cm tall with very narrow sword shaped leaves and a spike of several pink flowers, usually growing in thin soils and crevices of rocky outcrops within escarpment miombo woodland.

The second endemic Gladiolus species, Gladiolus virgineus, has only been collected once, at the time of writing this article, in 2018 and also grows on rocky outcrops within escarpment miombo woodland of central Zambia. It is slightly taller than G. serenjensis, growing up to 70 cm tall with narrow linear/lanceolate leaves and a spike of several pure white flowers with purple median markings on each of the lower 3 tepals.

Currently, neither of Zambia’s endemic Gladioli species are protected, nationally or internationally. Both occur in small geographic areas with G. serenjensis at least occurring in the National Heritage protected site of Kundalila Falls.

Unfortunately, with an increase in artisanal mining of kopjes and inselbergs in central Zambia, the habitats of both G. serenjensis and G. virgineus are coming under increased threat. More work is needed to project and conserve both these lovely little species.