Dorstenia is a genus of about 170 species of tropical plants in the Moaceae plant family, belonging to the same family as the fig and mulberry. This genus is composed mostly of woody or herbaceous perennial shrubs and geophytes. Generally divided into succulent and non-succulent species, the plants in this genus are single-stemmed, making them look like a miniature palm tree. The most striking characteristic about these plants is the flower-like structures called hypanthodiums, from which fleshy and elongated inflorescence extend. It is from these structures that Dorstenia plants came to be called shield flowers in general.
One of the species most commonly grown in home gardens, D. foetida, is an example of a succulent Dorstenia. Endemic to the bushlands, rock outcrops, and open places in Africa and the Middle East, the stem of the D. foetida can grow to 0.5 feet (0.1 m) in diameter and 1.3 feet (0.4 m) in height. Meanwhile, the non-succulent D. contrajerva, also known as the torus herb, prefers light shade. Native to the Caribbean region, it can grow up to 1.5 feet (0.5 m).
In general, the leaves of the Dorstenia plants are broadly elliptical and light green to grayish green in color. Aside from its odd inflorescence, another characteristic that makes these plants popular with home gardeners is its method of propagation. When ripe, the seedpods explode and send the seeds flying up to 7 feet (2 m) in distance. Some species are self-fertile, while others such as the largest, D. gigas, needs two plants to produce seeds. Dorstenia plants can also be grown through cuttings, so long as when planted in pots there is enough room to expand laterally.
While these plants prefer consistent and generally warm temperatures, their water needs vary depending on the season of the year. During the summer months, regular to abundant watering is recommended. Only when the weather gets colder can they survive with less water. They can survive periods with no water at all, but the soil should not be completely dried out.
Several species of Dorstenia are valued in Africa, Central America, and South America for their anti-infection, anti-rheumatic, and febrifugal properties. A decoction from the leaves of the D. psilurus is used to treat cough, headache, and stomach pain in Cameroon. In Panama and Mexico, D. contrajerva leaves are used to fight against fever and snake venom. Aside from their medicinal uses, Dorstenia plants are also used in the preparation of food such as in the case of D. foetida, where the tubers are cooked and eaten in Oman, and D. psilurus, whose rhizomes are used as spices for the preparation of na’a poh in Cameroon.
