Family: Araceae
Species: Colocasia esculenta (L.) Schott
Common name: Taro, Elephant ear
Etymology
Colocasia derives from the ancient Greek word kolokasi, referring to the edibility of the rhizomes.
Description
A marsh plant and herbaceous perennial with a large rhizome situated above or just below the soil's surface.
The leaves of this plant are large and face downwards. They are shaped like an elongated heart, pale green in colour with prominent veins. They are mainly decorative and often have a wavy outline. Their appearance strongly recalls that of another species in the Araceae family, Philodendron.
Each plant can bear more than one inflorescence. C. esculenta has a yellowish-white inflorescence known as a spadix— a spike of tiny flowers enclosed by a large bract (a modified leaf that protects the flower and fruit from cold and parasites). This typical flower is rarely produced and is usually hidden by the foliage when it blooms; the plant is more likely to reproduce via its rhizomes.
The fruit is a berry, 3–5 mm in diameter, and contains numerous seeds.
Habitat
It is native to central-southern Asia, likely India or the Malay Peninsula, from where it spread to the rest of Southeast Asia and to China, Japan, and the Pacific. From Asia, it continued westward into the Mediterranean region. Having arrived on Africa’s east coast over 2,000 years ago, it crossed the continent to West Africa and later reached the Caribbean through the slave trade. Today, the largest area of cultivation is in West Africa. It is also naturalised in parts of Italy with a mild climate.
Properties and Uses
With appropriate preparation, it is employed as a medicinal plant to treat psoriasis.
Notes and Curiosities
The tuber—commonly known as taro—is edible and somewhat like a potato, with white or reddish flesh, and can be used to produce flour. The leaf stems are also edible after prolonged boiling. Taro forms a vital food source in many South American, African, and Asian regions. The cultivars that produce short, egg-shaped rhizomes are called “Eddo” (China and Japan), while those with long, creeping, cylindrical rhizomes—sliced before use—are known as “Dasheen” or “Taro” (Southeast Asia and southern India) and have lower organoleptic quality. Some cultivars produce rhizomes with purple pulp in Hawaii, and perhaps elsewhere, much prized for preparing local dishes.
In summer, taro thrives on abundant light, water, and fertiliser. In autumn, it requires simply moist rather than submerged soil. Cultivars with very tuberous rhizomes (usually used for food) can remain dry in winter. Other types, however, develop thin rhizomes (generally ornamental) that would not survive an arid winter, so they must be kept in growth conditions, in slightly moist soil, at a minimum of around 8–10 °C.
This species is widely present in the Heller garden as undergrowth in water-dominated areas. Thanks to its large leaves, the plant creates a striking visual effect throughout the park. The foliage is incredibly well developed, likely because the overhanging trees protect it from the intense afternoon sun.