The bite comes from the high content of oxalic acid, which means it should only be eaten in moderation. Sorrel appears soon after winter, so is good for salads early in the year when there is little else around. It has one of the largest roots of all vegetables and lives a long time.

Varieties
Garden sorrel (Rumex acetosa) and sheep's sorrel (Rumex ascetosella) are indigenous to Britain. Cultivated French sorrel (Rumex scutatus) tastes very similar though the leaves are a different shape. Wood sorrel is a completely different plant, though also a traditional herb used for soups and salads.


Serving suggestions
When the leaves are under 7.5cm long, they can be used raw in salads, especially with dandelion leaves. Bigger leaves can be made into soups, sauces and risotto. Khaki-coloured sorrel purée is a good acidic accompaniment to oily fish, chicken or veal, or poached eggs on toast. It can be stirred into crème fraîche to give quick sauce. Add a few leaves of watercress, spinach or parsley if you want a brighter green colour. Chop sorrel like a herb to add to stuffings and crumb coatings. The lemony taste means sorrel can also be added carefully to fruit salads, jellies, custard and fruit drinks, as lemon balm or verbena.

Preparation
Strip large leaves from their stalks: fold the leaf in half lengthways so the back ridge is outwards and the stalk points up, then tear the stalk away along the length of the leaf. You don't need to add water when cooking sorrel - like spinach you can just place the washed, dried leaf in a pan and cook over a low heat.