sorrelthumb.jpg19 August 2013 - Sorrel is a common plant of grazed or infrequently-mowed fields - I picked some lovely tangy sorrel leaves in a steeply sloping pasture in Somerset - just below Wimbleball Dam.

What Is Sorrel?

sorrel1.jpgRumex acetosa - a relative of common dock, rhubarb and buckwheat.

It has fresh green oval leaves, up to about 10cm long with an arrow-shaped base, borne on slender arching stalks.

sorrel2.jpgThe most conspicuous part of the plant is the upright flower stalk which grows up to about a metre tall, bearing branching side shoots densely covered with small bright pinkish-red flowers.

This is a good way to distinguish it from common dock - which has similar flower structures but they are thicker in growth and green, turning to deep brown as they ripen.

sorrel3.jpgThe leaves are easily recognisable by means of the distinctive V-shaped arrowhead cutout at the stalk end.

NB: there are other plants with arrowhead-shaped leaves - most notably including the plants of the arum family, but you're unlikely to mistake those for these, especially if you're looking in an open grassy habitat, and have already located sorrel by its flower spikes.

The leaves have a delicious fresh acidity to them - most often compared to the flavour of lemons, but in my view, more similar to raw gooseberries or sour green grapes - these make a welcome and refreshing addition to salads or sandwiches.

Sheep's Sorrel

sorrel4.jpgA similar and closely-related plant is Sheep's Sorrel (Rumex acestosella) - this one is more commonly found as a spreading weed in mowed or more closely-grazed grass.

It's a broadly similar plant - the leaves (not clearly shown here) are narrower and have a more distinct arrowhead shape, but it can be used in exactly the same way as common sorrel.

Wood Sorrel

sorrel5.jpgRelated only in name, this plant (Oxalis acetosella) is common on damp, shady woodland floors and riverbanks.

It has delicate, bell-shaped, five-petalled white flowers in spring and trifoliate leaves, each leaflet being heart-shaped with a conspicuous central crease.

Like its unrelated namesake, the leaves of wood sorrel have a sharp acid flavour - which in this plant is quite concentrated, so it is best used sparingly in a salad of mixed leaves, or as a garnish.

Sorrel And Oxalic Acid

The acidity in sorrel comes chiefly from oxalic acid - which in large doses is toxic, but nothing to worry about in the small quantities contained in a handful or two of these leaves that you might typically pick and eat.

However, the toxicity of large doses of oxalic acid is related to kidney function - the substance combines with calcium to form calcium oxalate crystals. For this reason, it should be avoided by anyone with:

  • a history of kidney problems
  • problems obtaining enough calcium from their diet
  • gout, arthritis or other inflammatory joint problems (the oxalate crystals can form in the joints)

This is not intended to put anyone off trying this wild herb - it's widely eaten as a wild picked or cultivated vegetable, without any ill effect for the majority of people.