The term “Elephant Ears” is a popular common name used to refer to several different species of tropical plants that share the characteristic of having dramatically large, often heart- or arrow-shaped leaves. Native primarily to the tropical and subtropical regions of Asia, the Pacific, and the Americas, these plants are highly valued in landscaping for their bold, architectural foliage. Their impressive size and lush, exotic appearance make them a favored choice for creating a tropical feel in gardens and containers. Understanding the botanical differences between the types of plants referred to as Elephant Ears is important for proper care and safety.
Identifying the Elephant Ear Plants
The plants most commonly sold under the name “Elephant Ears” belong to three distinct genera within the Araceae family: Colocasia, Alocasia, and Xanthosoma. While all three share the signature large leaf, they are distinguished by the orientation of their leaves and the specific point where the leaf stem, or petiole, attaches to the leaf blade. Knowing these physical distinctions helps determine the plant’s specific cultural needs and its ultimate size.
Colocasia
Colocasia species, which include the common edible taro (Colocasia esculenta), are characterized by leaves that typically point downward or cascade, giving the plant a drooping appearance. The petiole attaches to the center of the leaf, away from the edge, creating a peltate or “umbrella-like” structure. This attachment point is a reliable identifier for Colocasia, which often prefers consistently wet or even boggy soil conditions.
Alocasia
In contrast, Alocasia species, sometimes called Upright Elephant Ears, are recognized because their leaves aim upward or outward toward the sky. The petiole attaches directly to the notched edge of the leaf blade, not the center. Alocasia generally prefers well-drained but consistently moist soil, and many varieties are also known for having leaves with more textured or intricate venation.
Xanthosoma
The third genus, Xanthosoma, is often referred to as Malanga or Cocoyam and tends to hold its leaves horizontally or with a slight downward angle. Similar to Alocasia, the leaf stem attaches at the leaf notch. Xanthosoma leaves are often distinctly arrow-shaped (sagittate) with a waxy coating and prominent veining.
Understanding Toxicity and Health Safety
The primary health concern associated with all raw Elephant Ear plants, including Colocasia, Alocasia, and Xanthosoma, is their toxicity due to the presence of calcium oxalate crystals. These microscopic, needle-shaped crystals, known as raphides, are stored within specialized cells in all parts of the plant, including the leaves, stems, and corms. When any part of the raw plant is chewed or ingested, the raphides are released and physically penetrate the soft tissues of the mouth, throat, and gastrointestinal tract.
This physical irritation immediately triggers a localized inflammatory response, leading to a painful burning sensation in the mouth, lips, and tongue. Common symptoms following raw ingestion include drooling, oral pain, swelling of the throat, and difficulty swallowing (dysphagia). In rare but serious instances, significant swelling of the upper airway can occur, potentially leading to breathing difficulties and requiring medical intervention.
Due to this mechanism of toxicity, all Elephant Ear plants should be kept out of reach of children and pets. Handling the raw plant material can also cause skin irritation or contact dermatitis in sensitive individuals. Any plant material intended for consumption must be subjected to extensive cooking or processing, which effectively neutralizes the irritating calcium oxalate crystals.
Cultivation and Care Requirements
Elephant Ear plants are generally grown as tropical foliage specimens, requiring a warm environment to thrive and achieve their maximum size. They prefer locations that offer partial shade or filtered sun, especially in hot climates where intense afternoon sun can scorch the large, tender leaves. However, many Colocasia varieties can tolerate full sun exposure, provided they receive an abundance of water.
These plants are native to environments with high moisture and humidity, making consistent watering a requirement throughout the active growing season. Colocasia is particularly moisture-loving and is often planted in boggy areas or near water features where the soil remains perpetually saturated. Alocasia and Xanthosoma still require moist soil but typically prefer better drainage to prevent their corms from rotting.
In North America, Elephant Ears are reliably hardy only in USDA Zones 7 through 11, meaning they are treated as annuals in colder regions. To preserve the corms or tubers, they must be dug up after the first frost, allowed to dry, and then stored in a cool, dark, and dry location that remains above freezing. They can then be replanted the following spring once all danger of frost has passed.
Culinary Uses and Common Misunderstandings
While most Elephant Ears are grown solely as ornamentals, the corm of one species, Colocasia esculenta, is an ancient and widely cultivated food staple known as taro. This starchy, edible underground stem, along with the leaves and stems, is consumed across Africa, Asia, and the Pacific Islands under names like taro, eddoe, and dasheen. The corms are rich in complex carbohydrates and have a slightly nutty or sweet flavor when cooked.
To make taro safe for consumption, the raw corm must be thoroughly cooked, often by boiling, steaming, or baking, to break down and dissolve the irritating calcium oxalate crystals. Traditional preparations such as the Hawaiian paste poi, which is made from pounded, cooked taro corms, exemplify the necessary processing. The leaves are also eaten as a cooked vegetable, but they also require the same extensive cooking to neutralize the toxicity.
The common name “Elephant Ears” also refers to a popular, non-plant item: a large, flat, deep-fried pastry found at carnivals, fairs, and amusement parks. The yeast-based dough is stretched thin, fried until crispy, and then traditionally dusted with cinnamon and sugar.