Rumex hydrolapathum

Huds.

Great water dock, Wild rhubarb

PolygonaceaeLeavesRootsPotential hazards — see below

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What to Eat

Edible parts: Leaves, Root

Young leaves are edible when cooked. The seed can be eaten raw or cooked, and may be ground into a flour, though it is small and rather fiddly to harvest.

Known Hazards

Plants can contain quite high levels of oxalic acid, which is what gives the leaves of many members of this genus an acid-lemon flavour. Perfectly alright in small quantities, the leaves should not be eaten in large amounts since the oxalic acid can lock-up other nutrients in the food, especially calcium, thus causing mineral deficiencies. The oxalic acid content will be reduced if the plant is cooked. People with a tendency to rheumatism, arthritis, gout, kidney stones or hyperacidity should take especial caution if including this plant in their diet since it can aggravate their condition.

Where to Find It

It is a temperate plant. It grows in wet places. It can grow in shallow water.

Asia, Australia, Britain, China, Europe, France, Slovenia, Turkey, Türkiye,

Countries: Andorra, United Arab Emirates, Afghanistan, Albania, Armenia, Austria, Australia, Azerbaijan, Bosnia & Herzegovina, Bangladesh, Belgium, Bulgaria, Bahrain, Brunei, Bhutan, Belarus, Switzerland, China, Cyprus, Czechia, Germany, Denmark, Estonia, Spain, Finland, France, United Kingdom, Georgia, Greece, Croatia, Hungary, Indonesia, Ireland, Israel, India, Iraq, Iran, Iceland, Italy, Jordan, Japan, Kyrgyzstan, Cambodia, North Korea, South Korea, Kuwait, Kazakhstan, Laos, Lebanon, Liechtenstein, Sri Lanka, Lithuania, Luxembourg, Latvia, Monaco, Moldova, Montenegro, North Macedonia, Myanmar, Mongolia, Malta, Maldives, Malaysia, Netherlands, Norway, Nepal, Oman, Philippines, Pakistan, Poland, Portugal, Qatar, Romania, Serbia, Russia, Saudi Arabia, Sweden, Singapore, Slovenia, Slovakia, San Marino, Syria, Thailand, Tajikistan, Timor-Leste, Turkmenistan, Turkey, Taiwan, Ukraine, Uzbekistan, Vietnam, Yemen

How to Identify

A robust plant which keeps growing from year to year. It grows 1.2-2 m high. In shallow water it produces aerating roots. The leaves are narrow and dark green. They are spear shaped and 1 m long. The flowers are in a brownish-pink spike. They are on stalks 2 m long.

How to Grow

Requires a moist or wet soil, also succeeding in shallow water. Avoids acid conditions in the wild. A very important food plant for the caterpillars of many species of butterfly.

Propagation: Sow seed in spring in situ. Can also be propagated by division in spring.

Medicinal Uses

The root is antiscorbutic and strongly astringent. It is harvested in early spring and dried for later use. Green leaves are considered an excellent topical treatment for ulcers of the eyes.

Other Uses

The roots contain tannin — plants grown on dry land yield 6–8%, while those grown in water yield 12.4–21.6%. The dried and powdered root makes a good tooth cleaner. Roots yield dark green to brown and dark grey dyes without the need for a mordant.

Wikipedia

Source ↗

Rumex hydrolapathum, the great water dock, water dock, or giant water dock, is a species of perennial herbaceous plants in the genus Rumex native to fens and freshwater banks of Europe and Western Asia. It is the tallest species in the genus, with flowering stems attaining a height of up to 2 m (6 ft 7 in). It is one of the small number of decaploid organisms, containing two hundred individual chromosomes.

Notes

There are about 200 Rumex species.

Names & Synonyms

Eksi ot, Konjska kislica

Lapathum aquaticum Garsault [Invalid]Lapathum giganteum OpizLapathum hydrolapathum Scop.Lapathum maximum MontandonLapathum rivale P.Renault

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