Ipomoea aquatica

Ipomoea aquatica is a semi-aquatic, tropical plant grown as a vegetable for its tender shoots and leaves. It is found throughout the tropical and subtropical regions of the world, although it is not known where it originated. This plant is known in English as water spinach, river spinach, water morning glory, water convolvulus, or by the more ambiguous names Chinese spinach, Chinese Watercress, Chinese convolvulus, swamp cabbage or kangkong in Southeast Asia. Occasionally, it has also been mistakenly called 'kale' in English, although kale is a variety of cabbage and is completely unrelated to water spinach, which is a species of morning glory. It is known as phak bung (ผักบุ้ง) in Thai and Laotian, vung chhoi in Hakka, eng chhai in Teochew and Hokkien, ong choy (蕹菜) in Cantonese, kongxincai (空心菜) in Mandarin Chinese, rau muống in Vietnamese, kangkong in Tagalog, kangkung in Indonesian, Malay and Sinhalese, gazun (ကန်စွန်း) in Burmese, trokuon (ត្រកួន) in Khmer, kolmou xak in Assamese,'வள்ளல்' (vallal) in Tamil, kalmi saag in Hindi, kalmi shak (কলমি শাক) in Bengali, Thooti Koora in Telugu, Karmata Bhaji in Chhattisgarhi, Kalama Saga ('କଳମ ଶାଗ') in Odia, hayoyo in Ghana. In Suriname it is known as dagoeblad or dagublad. Ipomoea aquatica grows in water or on moist soil. Its stems are 2–3 metres (7–10 ft) or longer, rooting at the nodes, and they are hollow and can float. The leaves vary from typically sagittate (arrow head-shaped) to lanceolate, 5–15 cm (2–6 in) long and 2–8 cm (0.8–3 in) broad. The flowers are trumpet-shaped, 3–5 cm (1–2 in) in diameter, and usually white in colour with a mauve centre. Propagation is either by planting cuttings of the stem shoots that will root along nodes or planting the seeds from flowers that produce seed pods. Ipomoea aquatica is most commonly grown in East, South and Southeast Asia. It flourishes naturally in waterways and requires little, if any, care. It is used extensively in Indonesian, Burmese, Thai, Lao, Cambodian, Malay, Vietnamese, Filipino, and Chinese cuisine, especially in rural or kampung (village) areas. The vegetable is also extremely popular in Taiwan, where it grows well. During the Japanese occupation of Singapore in World War II, the vegetable grew remarkably easily in many areas, and became a popular wartime crop. In the Philippines, a variety of kangkong is grown in canals dug during the American occupation after the Spanish–American War, while another variety growing on land is called Chinese kangkong. In non-tropical areas, it is easily grown in containers given enough water in a bright sunny location. It readily roots from cuttings. Ipomoea aquatica is listed on the USDA internet site as a 'Class A noxious weed', especially in the states of Florida, California, and Hawaii, where it can be observed growing in the wild. I. aquatica has been extensively cultivated in Texas for over 30 years, having been originally brought there by Asian immigrants. Because no evidence indicates the plant has escaped into the wild, Texas lifted its ban on cultivation for personal use with no restrictions or requirements, noting its importance as a vegetable in many cultures, and also began permitting cultivation for commercial sales with the requirement of an exotic species permit. In Sri Lanka, it invades wetlands, where its long, floating stems form dense mats which can block the flow of water and prevent passage of boats. The vegetable is a common ingredient in East, South and Southeast Asian dishes, such as in stir-fried water spinach. In Singapore, Indonesia, and Malaysia, the tender shoots along with the leaves are usually stir-fried with chili pepper, garlic, ginger, dried shrimp paste (belacan/terasi) and other spices. In Penang and Ipoh, it is cooked with cuttlefish and a sweet and spicy sauce. Also known as eng chhai in the Hokkien dialect, it can also be boiled with preserved cuttlefish, then rinsed and mixed with spicy rojak paste to become jiu hu eng chhai. Boiled eng chhai also can be served with fermented krill noodle belacan bihun and prawn mi. In Indonesian cuisine it is called kangkung, boiled or blanched together with other vegetables it forms the ingredient of gado-gado or pecel salads in peanut sauce. Some recipes that use kangkung is plecing kangkung from Lombok, and mie kangkung (kangkong noodle) from Jakarta.