Sorrel

Rumex acetosa

Family: Polygonaceae Part used: Leaves

Key Compounds

• Oxalic acid
• Potassium hydrogen oxalate
• Vitamin C
• Flavonoids (quercetin, hyperoside)
• Tannins
• Anthraquinones
• Malic acid
• Citric acid
• Mucilage

Traditional Use

• Culinary food herb (primary use) — sorrel is first and foremost a food plant; the leaves are eaten in salads, soups, sauces, and as a cooked vegetable across European cuisines; French *soupe à l'oseille*, Ashkenazi Jewish *schav* (cold sorrel soup), Eastern European sorrel borscht, and Egyptian adas bel hamoud are the most documented culinary traditions; the culinary use provides vitamin C, flavonoids, and organic acids at dietary quantities that do not constitute a medicinal dose but provide genuine nutritional value
• Mild diuretic and cooling — traditional European and folk application; oxalic acid and the plant's overall acidity produce a diuretic effect; the 'refrigerant' property — a traditional category for plants used to cool fever and inflammation — reflects the plant's acidic, cooling flavour and mild anti-inflammatory effect; used in hot weather and febrile conditions for their cooling quality; the evidence base is traditional rather than clinical
• Antiscorbutic (historical) — vitamin C content supported pre-modern use for scurvy prevention; the leaves contain 75–119 mg/100g vitamin C (comparable to orange juice); sailors and expeditionary parties have used sorrel as a fresh green source of vitamin C; the oxalic acid concern is real but at reasonable dietary quantities is not a practical problem for most healthy people; the antiscorbutic application preceded knowledge of vitamins and is described in European naval and expedition medicine from the 17th–19th centuries
• Mild laxative — anthraquinone content (same compound class as senna and rhubarb, both also Polygonaceae) provides mild stimulant laxative effect at higher doses; this application is incidental to culinary use rather than a therapeutic focus; large quantities of sorrel as food can have noticeable laxative effects, particularly in children

The name means sour. In every language it has.

‘Sorrel’ is from Old French surele, from Frankish sur (sour). Acetosa — the Latin species name — is from acetum, vinegar. French oseille traces through the same root. German Sauerampfer is literally ‘sour dock.’ Whatever language you start in, you end up describing the taste. This is a plant that was named, independently, in every European language by people tasting it rather than examining it in any other way.

The sour flavour is oxalic acid. The oxalic acid is also what puts kidney stone patients on restricted diets. It is the same compound that makes rhubarb leaves toxic at concentration. And it is the same compound that gives spinach its slight earthiness, wood sorrel its bright sharpness, and sorrel its intense lemony bite.

It is also a very good soup.

Meet the plant

A perennial with arrow-shaped basal leaves, reddish flowering stems to 60–120 cm, and inconspicuous reddish-green flowers that are wind-pollinated. The leaves are the part used — harvested in spring when young, tender, and least bitter. The plant is dioecious (male and female flowers on separate plants), which is unusual in the dock family. Grows in meadows, roadsides, and garden borders in temperate Europe, Asia, and North America.

The oxalic acid situation

Oxalic acid — the source of sorrel’s flavour — is present at 700–1200 mg/100g of fresh leaf. For reference:

• Spinach: 600–1000 mg/100g
• Rhubarb leaves (toxic): 5000+ mg/100g
• Rhubarb stalk (edible): 450–900 mg/100g
• Tea: 150–900 mg/100g (brewed)

At culinary quantities — a handful of leaves in a salad, a bowl of sorrel soup — the oxalic acid load is comparable to eating spinach. It is not a concern for most healthy adults with adequate fluid intake. The calcium-binding effect is real but doesn’t meaningfully affect nutrition at normal dietary portions.

The concern applies specifically to: people with calcium-oxalate kidney stones (or family history); people with kidney disease; people taking large doses as medicine rather than eating it as food.

The soup traditions

Sorrel’s most significant cultural presence is in its culinary use — specifically in the sour green soups of Central and Eastern Europe.

Soupe à l’oseille (France): Sorrel cooked until it wilts into a dark olive purée, combined with stock and cream. A spring staple of French regional cooking from at least the 17th century. The colour — greenish-grey — comes from the oxalic acid reacting with the protein in cream.

Schav (Ashkenazi Jewish): Cold sorrel soup from Eastern European Jewish cooking, served chilled in summer, typically with sour cream. One of the signature flavours of Ashkenazi summer cooking. Still available in some delicatessens in New York.

Sorrel borscht (Eastern Europe): Similar to schav but varying by region and tradition — the sour green version of beet borscht.

In all of these traditions, sorrel is used as a fresh seasonal spring herb, picked when the leaves are young and tender. The season is short — April to June — before the leaves become tough and more bitter with heat.

The antiscorbutic history

Before citrus was reliably available to European sailors, fresh spring greens were the primary practical source of vitamin C. Sorrel, with 75–119 mg/100g in fresh leaves (comparable to orange juice), was used as a fresh green source.

The antiscorbutic application is well-documented in European military and expedition medicine from the 17th–19th centuries. Cooks on long voyages or overwintering expeditions who could access fresh sorrel (it survives mild winters and is among the first spring plants to produce usable leaves) used it for its vitamin C.

The oxalic acid concern was not clearly understood until much later. The practical reality: at the quantities available from wild-gathered fresh greens, the antiscorbutic benefit outweighed the oxalate risk. Therapeutic quantities of dried leaf tea for the same purpose would have a different risk-benefit balance.

What people actually do with it

Culinary (primary use): Fresh young leaves in salads, combined with other mixed greens. Cooked in sauces for fish and eggs. Incorporated into soups and stews. The French sauce verte (sauce à l’oseille) — a classic accompaniment to salmon and other fish. The culinary use is the most authentic application of this plant and represents genuine nutritional value.

Infusion (folk medicine): 1–2 teaspoons dried leaf per cup, steeped 5–10 minutes. 1–2 cups daily for diuretic and cooling effects. Not for prolonged use due to cumulative oxalate intake.

Fresh juice: Traditional cooling drink — fresh leaves juiced or blended with water. Used as a fever drink in traditional European medicine.

Could you grow this yourself?

Yes, and it is one of the more rewarding culinary herbs to grow. Sorrel is perennial, requires almost no maintenance, and produces usable leaves from early spring to late autumn. Plant in a sunny to partially shaded spot in moist soil. Cut the flowering stem before it sets seed to keep the plant producing leaves. Once established, a plant will last years without replanting. Harvest the outer leaves and the plant continues producing. French sorrel (R. scutatus) has a milder, less acidic flavour than common sorrel and is preferred by some cooks — it is smaller and lower-growing.

Sorrel (スイバ) in Japan

スイバ (suiba) grows wild throughout Japan and is found in meadows, roadsides, and disturbed ground. Japanese traditional medicine has limited specific sorrel applications — the plant is not a significant kampo herb. The broader Polygonaceae family is represented in Japanese medicine primarily by 大黄 (daiō, Chinese rhubarb, Rheum palmatum) for laxative applications, not by Rumex.

Sorrel as a culinary herb follows Western European cuisine influence in Japan — oseille (oseille is used as a loanword in French-influenced Japanese cooking) appears occasionally in restaurant contexts. The traditional Japanese spring green that occupies a comparable food-herb role is タラノメ (Aralia elata shoots) or セリ (Oenanthe javanica) — different plants but similar seasonal spring green significance.

Things you’re probably wondering

Is sorrel the same as wood sorrel? No. Rumex acetosa (common sorrel) is in the dock family (Polygonaceae). Wood sorrel (Oxalis acetosella) is in the Oxalidaceae — an entirely different family. Both have a sour, oxalic-acid flavour, which is why both share the ‘sorrel’ name. Wood sorrel actually has a higher oxalate content than common sorrel. French sorrel (R. scutatus) is a third ‘sorrel’ — a Rumex species like common sorrel but smaller-leaved and milder.

Can you use dried sorrel? The vitamin C content — sorrel’s most significant antiscorbutic compound — degrades rapidly on drying. Dried sorrel retains its flavonoids, tannins, and some of its mineral content but loses most of its vitamin C. For culinary purposes and for the cooling/antiscorbutic applications, fresh leaves are the appropriate form. Dried sorrel is used in folk medicine for the diuretic and laxative applications, where vitamin C is not the relevant compound.

Botanical details

The full compound list

See Also

• Wood Sorrel — different family, same sour taste, same oxalate chemistry; smaller plant, same spring foraging context
• Yellow Dock — Rumex crispus, same genus; higher anthraquinone content; more established as a medicinal laxative
• Chickweed — spring green herb; similar culinary and nutritive tradition

References

• Grieve, M. (1931). A Modern Herbal. Dover.
• Duke, J.A. (1992). CRC Handbook of Biologically Active Phytochemicals and Their Activities. CRC Press.
• Harborne, J.B. & Williams, C.A. (2000). Advances in flavonoid research since 1992. Phytochemistry, 55(6), 481–504.
• British Herbal Pharmacopoeia. (1983). British Herbal Medicine Association.