Ipomoea aquatica

BOTANICAL NAME:- Ipomoea aquatica
Syn :- I. reptans, I. repens


SINHALA : Kankun 
TAMIL : Koilangu, Sarkareivalli, Kankun
ENGLISH : Kang kong, Swamp cabbage, Water convolvulas, Water Spinach. 


Annual or biennial herb with long prostrate stems rooting at nodes, thick, hollow, glabrous, internodes 7-14 cm long.

LEAVES:- Simple, alternate without stipules, 5-12 cm long, 4.5-7 cm broad, ovate-oblong, the base usually dilated and hastate with rounded or acute lobes, glabrous, petioles as long as or longer than leaves.

FLOWERS:- Regular,bisexual, rather large, dull purple on long glabrous pedicels, usually solitary, often 2, peduncle much shorter than the petiole. (period-August to November) (Jayaweera, 1980).


Grows in damp places throughout India, Sri Lanka, Burma and Philippines. Often cultivated as a pot herb. It also grows in Africa and Australia. In Sri Lanka it is common in shallow water and moist places in dry regions. There are two forms in cultivation - 1, semi aquatic form, 1.aquatic a var, aquatica, ii. land form. aquatica var.raptans (Rice et al., 1993; Tindall, 1993).

EDIBLE PARTS : The leaves and part of the prostrate stem.
FOOD USE: The leaves and the parts of the prostrate stems are used as a cooked vegetable


Moisture - 90.3 g, 
Energy -28 kcal, 
Proteins -2.9 g, 
Fats -0.4 g, 
Carbohydrates -3.1 g, 
Minerals - Calcium - 110 mg, 
Phosphorus - 46 mg, 
Iron - 3.9 mg - Carotene 1.98 meg, 
Thiamine 50 meg, 
Riboflavin 130 meg, 
Niacin - 0.6 mg, 
Vitamin C-137 mg (Perera et. al., 1979).

It is an excellent source of Iron, Calcium, Vitamins B and C. The plant is mildly laxative and owing to the presence of insulin-like principle, it is used against diabetes mellitus. The bud is applied on ringworm (Jayaweera, 1985; Pauda et al., 1987).

OTHER USES: The wine is used as fodder for cattle and pigs.


Adopted to a wide range of soil conditions but clay soils with high temparatures are more suitable. Requires high moisture content of the soil. Normally grows in lowlands and short day lengths.


Areas for cultivation - Wet zone and moist places closer to irrigated tanks in the dry zone; the semi-aquatic form is after grown in places which are subjected to flooding.

Planting season - Almost throughout the year.

Land preparation - Land has to be worked to a fine condition and make seed beds.

Planting material - Stem cuttings.

Planting and space - Stem cuttings are planted in rows. Distance between two plants is around 40-45 cm.

Irrigation - Proper irrigation during day periods increases the yield of land form.

Fertilizer - Organic manure will increase the harvest

Time to harvest - The first harvest is 50 days after planting. Then harvesting can be done through the year if irrigation is available.

Harvest - Cut back to the two leaves above the bottom.  Yield - 4-6 ha given by semi-aquatic forms, the land form gives approximately 50% less.


Harvest is kept for 1-2 days under normal conditions.