Rumex vesicarius aka Bladder Dock

Rumex vesicarius is also known as bladder dock. It belongs to the plant family Polygonaceae. Its native range runs from Macaronesia east to Myanmar. It spans North Africa, Arabia, Iran and India. Kew lists it as an annual from subtropical regions. Annual plants live for one year. Useful Tropical Plants also notes forms that live for years. These have rhizomes, which are stems that grow below ground. It is not native to Britain or Ireland.

This herb grows about 1.6 feet [0.5 metres] tall. Many branches grow from the base of the plant. In the wild, it grows among loose stones in dry places. It also grows on grassy slopes and slopes with gravel. Its habitats range from sea level to 3,773 feet [1,150 metres]. Wind carries the plant's pollen. The supplied sources give no flower or fruit details for this species.

Bladder dock comes from dry places with warm climates. These span warm temperate zones through to the tropics. Growers have had some success in humid Tanzania too. In gardens, it prefers sun and moist soil that drains well. It suits soil with a fair level of nutrients. It will grow in most soils, though. Sow the seed straight into the site where it will grow. The sources give no frost limit or hardiness zone. Its dry wild homes alone do not show its garden water needs.

People pick leaves from wild plants for local meals. Some growers in Indonesia raise it as a leaf crop. They also sell the leaves in local markets there. People eat them raw or cook them as a vegetable. Their sour taste suits salads and use as a flavouring. People also cook them as greens, much like spinach. Food is the main garden use that these sources record. Useful Tropical Plants also notes folk uses for leaves, seeds and juice. People use these to ease constipation, toothache and nausea. They also use them to treat dysentery. These records do not prove that the treatments work.

The leaves contain oxalic acid. Large servings thus pose risks. This acid can bind calcium and limit the body's access to minerals. Cooking cuts the amount of oxalic acid. People prone to kidney stones or gout need extra care. The source also warns people with arthritis, rheumatism or hyperacidity. Small food portions differ from large amounts. Outside its range, bladder dock can become a weed that persists. Reports from Australia say the plants can be hard to remove.