Rumex bucephalophorus aka Ruby Dock

Rumex bucephalophorus has the common name red dock. It is in the knotweed family, Polygonaceae. Kew lists it as an annual from the Mediterranean region. Its range spans the south of Europe and North Africa. It also covers parts of western Asia. Records list Portugal, Spain, France, Italy, Greece, and Turkey. It grows in Cyprus, Lebanon, Syria, and Israel too. North African records list Morocco, Algeria, Tunisia, Libya, and Egypt. PFAF also lists several islands in the Atlantic. The RHS says it is not native to Britain or Ireland.

Red dock grows on sand and rocks, often near the sea. Kew places it in the subtropical climate zone. PFAF says it may be annual or perennial. This means it may live one year or more. Kew lists it only as an annual. The sources give no height or spread for this species. They give few clear facts about its stems and leaves. They do not confirm flower colour, fruit form, or bloom dates. Each flower has both male and female parts. Wind moves pollen from flower to flower.

PFAF lists sand, loam, and clay as suitable soils. Soil may be mildly acid, neutral, or mildly alkaline. It needs good drainage but accepts dry to moist soil. It can grow in sun or light shade. PFAF says it can cope with winds from the sea. Its growing notes stress how little is known about this species. They draw in part on the needs of related plants. No firm rating exists for its hardiness in British winters.

PFAF lists garden beds as one place to grow it. It says to sow seed in a cold frame in spring. Once seedlings grow large enough, move each to its own pot. The young plants can then move outside in summer. The sources confirm no role for it as an ornamental plant. Nor do they give its size in a landscape. They name no pests or diseases for this species. PFAF does not flag it as a weed risk.

PFAF lists the leaves as edible but rates their food use low. One other report says to cook the plant. It does not name which part to use. The hazard note warns of oxalic acid and large servings. Cooking cuts the amount of oxalic acid. This acid can reduce how much calcium the body can use. People prone to kidney stones or gout need extra care. PFAF also warns those with arthritis, rheumatism, or hyperacidity. It lists no known use of this species as medicine.