Description
Kang Kung is a creeping plant that has a hollow stem and can float on water. The leaves are green and are normally and depending on the variety, the shape and size of the leaves can vary. The flowers are trumpet shaped and white in colour. The runners develop roots at the nodes and also branch. This branching increases when tips are picked off. In Sri Lanka, it is commonly found growing wild in paddy fields, irrigation canals, and marshy areas. Kankung is so well-suited to growing in Sri Lanka that it is often considered an invasive plant, growing into mats that will block waterways. The USDA considers it a noxious weed.
Stir-fried kankung is one of the cheapest and most popular vegetable dishes in many parts of South Asia and South East Asia. In some ayurvedic practices, kankung is also recommended as a method of controlling blood sugar.
Planting requirements
Planting season: Year-round in Sri Lanka, but best planted at the onset of rainy seasons
Planting conditions:
| Propagation | In the drylands it is normally grown from seed but sometimes however the seeds are pre-soaked for 12-24 hours prior to sowing. Plants can also be grown from cuttings |
|---|---|
| Planting method | Can be grown in the pot (which is better as kangkung grows aggressively) or on the ground. You can also plant it near the edge of a pond or other water bodies |
| Soil | Requires a soil with a pH between 5.3–6.0. Damp places and swamps will be ideal for growing. It can also grow as a partly floating plant in swamps and lagoons behind a beach along the coast |
| Water | It needs consistently muddy soil |
| Light | It requires full sun to thrive, though it can grow in partial shade as well |
Growing conditions:
| Temperatures | Thrives in Sri Lanka's tropical climate with temperatures typically above 25°C |
|---|---|
| Soil | Requires evenly moist, wet, and nutrient-rich soil |
| Water | Unless planted next to a water body or stream, deep and regular watering is required to keep the soil nearly wet |
| Pruning | Regular harvesting of young shoots promotes bushy growth |
| Weed control | Hand weeding is usually sufficient in small-scale cultivation |
Harvesting
Can be harvested usually 4 to 6 weeks after planting. Cut only a few leaves or entire plant with leaves and stems leaving only 3 inches of growth, for the plant to regrow. In Sri Lanka, continuous harvesting is common, with new shoots ready for harvest every 1-2 weeks.
Curing
Kang-Kung does not require a curing stage.
Storage
Store in refrigerator crisper drawer for up to one week. In Sri Lanka, it's often sold fresh in markets and consumed within a day or two of harvest.
Protecting your plants
Pest control
Pest type:
- Leaf beetle
- Wireworm
- Aphids
Symptoms:
- Holes in leaves
- Damaged roots
- Stunted growth
- Curling leaves
Control method:
- Use soapy water or neem-based organic pesticides
- Implement crop rotation
- Remove infected plants
- In Sri Lanka, neem-based organic pesticides are commonly used
Disease Control
Disease type:
- Stem rot
- Root rot
- Leaf spot
- Mosaic virus
Symptoms:
- Wilting
- Yellowing leaves
- Dark spots on leaves
- Stunted growth
- Distorted leaves
Management:
- Improve soil drainage
- Avoid overwatering
- Remove and destroy infected plants
- Use disease-resistant varieties when available
- For viral diseases, control insect vectors like aphids
Sources
In addition to our General List of Sources (link), we used these specific references:
- https://worldcrops.org/crops/water-spinach
- https://fdc.nal.usda.gov/fdc-app.html#/food-details/169301/nutrients
- https://ausveg.com.au/biosecurity-agrichemical/crop-protection/asian-vegetables/
- Wiart, C. (2017). Medicinal plants in Asia for metabolic syndrome: natural products and molecular basis. CRC Press.
- Gunasekera, L. (2009). Invasive Plants: A guide to the identification of the most invasive plants of Sri Lanka. Saravasi, Sri Lanka.
- https://plants.usda.gov/java/noxious?rptType=Federal
