Persicaria attenuata

(R. Br.) Sojak

Watersmart weed, Hairy knotweed

PolygonaceaeLeaves

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What to Eat

Edible parts: Leaves, Vegetable

Leaves - raw or cooked. Used as a fresh salad or as a cooked vegetable. In South-East Asia the leaves are eaten with food as a tonic and to purify the blood. We have no specific information for this species, but the seed of most, if not all, members of the genus is edible both raw and cooked, and is potentially a good source of amino acids. Unfortunately the seed is also usually rather small and fiddly to utilize.

Where to Find It

A tropical plant. It grows on the edges of swamps and waterways. It grows from sea level to 1,000 m above sea level.

Africa, Asia, Australia, Benin, East Africa, East Timor, Eswatini, Indochina, Indonesia, Laos, Pacific, Papua New Guinea, PNG, SE Asia, Sierra Leone, South Africa, Southern Africa, Swaziland, Tanzania, Timor-Leste, West Africa, Zimbabwe,

Countries: United Arab Emirates, Afghanistan, Armenia, Angola, Australia, Azerbaijan, Bangladesh, Burkina Faso, Bahrain, Burundi, Benin, Brunei, Bhutan, Botswana, Congo (DRC), Central African Republic, Congo (Republic), Cote d'Ivoire, Cameroon, China, Cape Verde, Djibouti, Algeria, Egypt, Eritrea, Ethiopia, Fiji, Micronesia, Gabon, Georgia, Ghana, Gambia, Guinea, Equatorial Guinea, Guinea-Bissau, Indonesia, Israel, India, Iraq, Iran, Jordan, Japan, Kenya, Kyrgyzstan, Cambodia, Kiribati, Comoros, North Korea, South Korea, Kuwait, Kazakhstan, Laos, Lebanon, Sri Lanka, Liberia, Lesotho, Libya, Morocco, Madagascar, Marshall Islands, Mali, Myanmar, Mongolia, Mauritania, Mauritius, Maldives, Malawi, Malaysia, Mozambique, Namibia, Niger, Nigeria, Nepal, Nauru, New Zealand, Oman, Papua New Guinea, Philippines, Pakistan, Palau, Qatar, Rwanda, Saudi Arabia, Solomon Islands, Seychelles, Sudan, Singapore, Sierra Leone, Senegal, Somalia, South Sudan, Sao Tome & Principe, Syria, Eswatini, Chad, Togo, Thailand, Tajikistan, Timor-Leste, Turkmenistan, Tunisia, Tonga, Turkey, Tuvalu, Taiwan, Tanzania, Uganda, Uzbekistan, Vietnam, Vanuatu, Samoa, Yemen, South Africa, Zambia, Zimbabwe

How to Identify

A herb which keeps growing from year to year. It can grow in water or dry land. The stems are spreading. They can have long hairs. The sheaths are reddish-brown and 3 cm long. The leaves are 8-20 cm long by 1.5-5 cm wide. They are narrowly oval. The leaves are hairy. The flower spikes are 11 cm long by 1 cm wide. The flowers are about 0.4 cm long and white. The fruit are small nuts. They are dark brown to black.

How to Grow

Plants can be grown from seed or cuttings.

Medicinal Uses

Persicaria attenuata is widely used medicinally. The rhizome contains 2.5% of an acrid resin which is a depressant and can arrest the heart. The leaves are used in treatments for syphilis, rheumatism and swellings. They are eaten with food as a tonic and to purify the blood. The plant is burnt to obtain a vegetable salt which is rich in potassium and is applied to sores on the back and chest of scrofulous hunchbacked children.

Other Uses

The plant is considered an indicator of land suitable for rice cultivation.

Other Information

A locally used vegetable.

Notes

There are about 75-150 Persicaria species. There are about 20 in tropical America.

Names & Synonyms

Jankong, Jukut carang

Polygonum attentuatum R.Br.Polygonum pulchrum Blume

References (19)

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World Checklist of Useful Plant Species 2020. Royal Botanic Gardens, Kew