Lasia spinosa, known locally as Kohila (කොහිල), is a robust, evergreen herbaceous perennial that has been woven into Sri Lankan cooking and traditional medicine for centuries. Growing to between one and two metres in height, the plant spreads through long, creeping stoloniferous stems armed with stout prickles, making it instantly recognisable along the edges of paddy fields, riverbanks, and flooded lowlands across the island.
Where Does Kohila Grow in Sri Lanka?
Kohila thrives in waterlogged, nutrient-rich soils and is commonly found in the wet and intermediate zones of Sri Lanka. It colonises the margins of ponds, slow-moving streams, and irrigation channels, often forming dense stands. The plant is also cultivated on a small scale as a vegetable crop, particularly in low-country farming communities.
Beyond Sri Lanka, Lasia spinosa grows throughout tropical Asia — from India and Bangladesh through to southern China and Southeast Asia — wherever freshwater wetlands provide consistently moist conditions. In Sri Lanka, it is most frequently encountered in the lowland wet zone, though it can also be found in sheltered, moist pockets of the dry zone, often along waterways such as those within Madu Ganga, the expansive mangrove estuary near Balapitiya.
What Are the Edible Parts of Lasia spinosa?
The young leaves and the fleshy stem are the primary edible parts of the Kohila plant. In Sri Lankan kitchens, the stem — stripped of its outer skin and thorns — is sliced and cooked as a curry or stir-fry, typically with coconut milk, dried fish, and spices. The texture is firm and slightly mucilaginous, giving curries a characteristic body.
Kohila is valued both as an everyday vegetable and as a functional food. It is low in calories yet rich in dietary fibre, making it a common ingredient in home cooking across the southern and western provinces. Dehydrated Kohila root slices are also commercially available and used in herbal preparations.
How Is Kohila Used in Traditional Ayurvedic Medicine?
In Sri Lanka's ancient Sinhalese medical tradition — rooted in Ayurveda — Lasia spinosa holds a well-documented place as a multi-purpose medicinal herb. Practically every part of the plant, from the rhizome to the leaves and roots, is employed in different remedies.
- Leaves: Used to treat coughs, stomachaches, and digestive disorders, including constipation. Traditional preparations include leaf decoctions and poultices.
- Rhizomes and roots: Applied in treatments for lympho-tuberculosis, lymphonoditis, rheumatism, and as a topical remedy for snake and insect bites.
- Leaves and roots combined: Recommended for haemorrhoids (piles) and as a blood-purifying agent.
- General systemic use: Kohila preparations have been cited in ethnobotanical records for addressing lung inflammation, bleeding cough, sore throat, uterine conditions, intestinal diseases, and rheumatoid arthritis.
Ancient Sinhalese medical texts specifically reference the leaves as an aid for reducing symptoms associated with digestive problems, and the plant continues to feature in contemporary Ayurvedic formulations produced in Sri Lanka.
What Does Lasia spinosa Look Like?
The plant has a striking appearance that sets it apart from common wetland vegetation. Its stems are thick — around 2.5 cm in diameter — erect or ascending, and covered with prominent prickles along the internodes, which serve as a natural deterrent to browsing animals. The large, deeply lobed leaves are bright green and can reach impressive sizes, providing the plant with a bold, almost architectural profile.
The inflorescence is a spadix enclosed by a spathe, typical of the Araceae family to which Kohila belongs. Flowering is seasonal, and the plant reproduces both by seed and vegetatively through its creeping stolons, allowing it to colonise suitable habitats rapidly.
How Does Kohila Fit into Sri Lankan Food Culture?
Kohila curry (kohila mallum or kohila curry) is a staple in the home kitchens of southern Sri Lanka. Unlike more delicate vegetables, it requires relatively long cooking to soften the fibrous stem, but the result is a satisfying, earthy dish that pairs naturally with red rice or traditionally grown paddy varieties.
The plant also illustrates a broader principle in Sri Lankan culinary philosophy: the line between food and medicine is deliberately thin. Many of the vegetables served at a Sri Lankan table are chosen as much for their therapeutic properties as for their flavour. Kohila, with its known benefits for digestion and inflammation, exemplifies this tradition.
Is Lasia spinosa Related to Other Medicinal Plants?
Kohila belongs to the Araceae family and is the sole species in the genus Lasia. While it shares a family with the ornamental philodendron and the edible taro, it occupies a distinct ecological niche as a semi-aquatic plant. Sri Lanka is home to a rich pharmacopoeia of native medicinal plants; Kohila sits alongside species such as Pongamia pinnata (Karanda) in the canon of plants used in both traditional and contemporary Ayurvedic practice on the island.
How Is Kohila Harvested and Prepared?
Wild harvesting remains common in rural communities, where gatherers wade into shallow ponds and wetland margins to cut the stems at the base. Because the plant is stoloniferous and spreads vigorously, sustainable harvesting does not significantly deplete local populations. In cultivated settings, farmers plant Kohila along pond margins and harvest stems as needed throughout the year.
Preparation involves removing the thorny outer skin — typically done with a sharp knife — before slicing the stem into rounds or strips. The sliced stem is often soaked briefly in salted water to reduce any bitterness before cooking. For medicinal use, rhizomes may be dried, powdered, or prepared as a decoction depending on the condition being treated.
Can I Buy Kohila Products in Sri Lanka?
Fresh Kohila stems are widely available in local markets, particularly in the wet zone. Dehydrated Kohila root slices — convenient for travellers and those seeking a longer shelf-life herbal product — are produced by several Sri Lankan herbal brands and can be found in Ayurvedic pharmacies and speciality health stores. These products preserve much of the root's active compounds and are used in herbal teas and wellness preparations.
